Resveratrol induces long-lasting IL-8 expression and peculiar EGFR activation/distribution in human keratinocytes: mechanisms and implications for skin administration

Natural polyphenols for drug delivery and tissue engineering construction: A review

Polyphenols, natural compounds rich in phenolic structures, are gaining prominence due to their antioxidant, anti-inflammatory, antibacterial, and anticancer properties, making them valuable in biomedical applications. Through covalent and noncovalent interactions, polyphenols can bind to biomaterials, enhancing their performance and compensating for their shortcomings. Such polyphenol-based biomaterials not only increase the efficacy of polyphenols but also improve drug stability, control release kinetics, and boost the therapeutic effects of drugs. They offer the potential for targeted drug delivery, reducing off-target impacts and enhancing therapeutic outcomes. In tissue engineering, polyphenols promote cell adhesion, proliferation, and differentiation, thus aiding in the formation of functional tissues. Additionally, they offer excellent biocompatibility and mechanical strength, essential in designing scaffolds. This review explores the significant roles of polyphenols in tissue engineering and drug delivery, emphasizing their potential in advancing biomedical research and healthcare.

A comparative study of two aldehyde dehydrogenases from Sphingobium sp.: the substrate spectrum and catalytic mechanism

Biocatalytic oxidation is one of the most important and indispensable organic reactions for the development of green and sustainable biomanufacturing processes. NAD(P)+-dependent aldehyde dehydrogenase (ALDH) catalyzes the oxidation of aldehydes to carboxylic acids. Here, two ALDHs, SpALDH1 and SpALDH2, were identified from Sphingobium sp. SYK-6. They belong to different ALDH families and share only 32.30% amino acid identity. Interestingly, SpALDH1 and SpALDH2 exhibit significantly different enzymatic properties and substrate profiles. SpALDH2 has better thermostability than SpALDH1. SpALDH1 is a metalloenzyme and is activated by potassium ions, while SpALDH2 is not metallic-dependent. Compared with SpALDH1, SpALDH2 has a relatively broad substrate spectrum toward aromatic aldehydes. Based on homology modeling and molecular docking analysis, mechanisms underlying the substrate specificity of ALDHs were elucidated. For both ALDHs, hydrophobicity of substrate binding pockets is important for the catalytic properties, especially substrate specificity. Notably, optimization of the flexible loop 444-457 reforms a hydrogen bond between pyridine substrates and SpALDH1, contributing to the high catalytic activity. Finally, a coupling reaction catalyzed by ALDHs and NOX was constructed for efficient production of aromatic carboxylic acids.

Emerging Effects of Resveratrol on Wound Healing: A Comprehensive Review

Resveratrol (RSV) is a natural extract that has been extensively studied for its significant anti-inflammatory and antioxidant effects, which are closely associated with a variety of injurious diseases and even cosmetic medicine. In this review, we have researched and summarized the role of resveratrol and its different forms of action in wound healing, exploring its role and mechanisms in promoting wound healing through different modes of action such as hydrogels, fibrous scaffolds and parallel ratio medical devices with their anti-inflammatory, antioxidant, antibacterial and anti-ageing properties and functions in various cells that may play a role in wound healing. This will provide a direction for further understanding of the mechanism of action of resveratrol in wound healing for future research.

Fermented Mangosteen (Garcinia mangostana L.) Supplementation in the Prevention of HPV-Induced Cervical Cancer: From Mechanisms to Clinical Outcomes

Simple Summary

Human papillomavirus (HPV) is connected with virtually all cases of cervical cancer. The viral infection-associated chronic inflammation, oxidative stress, and alterations in apoptosis have been considered as leading risk factors for carcinogenesis in humans. In an observational clinical study, we identified oxidative markers and the cervical/circulating ligands of TNF-alpha-induced apoptosis involved in HPV-associated cervical carcinogenesis. In the following clinical trial, 250 females infected with high-cancer-risk HPV16/18 (healthy and pre-cancerous) were recruited into a placebo-controlled clinical study of supplementation with fermented mangosteen (FM, 28g/day, daily) for three months. Our findings indicate that FM, and not a placebo, in combination with routine anti-viral therapy, could prevent, slow down, or even interrupt HPV-associated cervical carcinogenesis, mainly through the suppression of leukocyte recruitment into infected tissue, through anti-inflammatory effects, and through the restoration of nitric oxide metabolite-initiated TRAIL-dependent apoptosis.

Abstract

In the observational clinical study, we identified the oxidative markers of HPV-associated cervical carcinogenesis and the local/circulating ligands of TNF-alpha-induced apoptosis. Cervical biopsies of 196 females infected with low-cancer-risk HPV10/13 or high-cancer-risk HPV16/18 (healthy, pre-cancerous CIN I and CIN II, and CIN III carcinoma) were analysed for OH radical scavenging, catalase, GSH-peroxidase, myeloperoxidase (MPO), nitrate/nitrite, nitrotyrosine, and isoprostane. Ligands of TNF-alpha-dependent apoptosis (TNF-alpha, TRAIL, IL-2, and sFAS) were determined in cervical fluid, biopsies, and serum. Cervical MPO was highly enhanced, while nitrotyrosine decreased in CIN III. Local/circulating TRAIL was remarkably decreased, and higher-than-control serum TNF-alpha and IL-2 levels were found in the CIN I and CIN III groups. Then, 250 females infected with HPV16/18 (healthy and with CIN I and CIN II) were recruited into a placebo-controlled clinical study of supplementation with fermented mangosteen (FM, 28g/day, daily) for three months. Post-trial colposcopy revealed normal patterns in 100% of the FM group versus 62% of the placebo group. Inflammatory cells in cervical fluid were found in 21% of the FM group versus 40% of the placebo group. Locally, FM drastically diminished MPO and NO₂/NO₃, while it remarkably increased TRAIL. Additionally, FM supplementation normalised serum TRAIL, TNF-alpha, and IL-2.

Kigelia africana inhibits proliferation and induces cell death in stage 4 Neuroblastoma cell lines

Neuroblastoma (NB) is one of the most common solid pediatric tumors and especially high-risk NBs still account for about 12-15% of cancer related deaths in children. Kigelia africana (KA) is a plant used in traditional African medicine which has already shown its anti-cancer potential in several in vitro and in vivo studies. The aim of this study is to evaluate the effect of KA fruit extract on stage 4 high-risk NB cells. Therefore, NB cell lines with and without MYCN amplification and non-neoplastic cells were treated with KA fruit extract at different concentrations. The effect of KA on cell viability and apoptosis rate were assessed by bioluminescence-/fluorescence-based assays. Several proteins involved in survival, tumor growth, inflammation and metastasis were detected via western blot and immunofluorescence. Secreted cytokines were detected via ELISA. Phytochemical composition of the extract was analyzed by liquid chromatography with tandem mass spectrometry (LC/MS/MS). Our group demonstrates a dose- and time-dependent selective cytotoxic effect of KA fruit extract on NB, especially in MYCN non-amplified tumor cells, by inhibiting cell proliferation and inducing cell death. Western blot and immunofluorescence results demonstrate a regulation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), disialoganglioside GD2 and epidermal growth factor receptor (EGFR) in KA-treated tumor cells. Our results evidence striking anti-cancer properties of KA fruit and pave the way for further surveys on the therapeutic properties and mechanisms of action in NB.

Resveratrol promotes skin wound healing by regulating the miR-212/CASP8 axis

The wound-healing process is a natural response to burn injury. Resveratrol (RES) may have potential as a therapy for wound healing, but how and whether RES regulates skin repair remains poorly understood. Human epidermal keratinocyte (HaCaT) cells were treated with lipopolysaccharide (LPS), and a mouse skin wound-healing model was established. Cell viability and apoptosis were analyzed by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide or flow cytometry. Cell proliferation was assessed by cell viability and colony-formation analyses. Cell migration was tested by wound-healing analysis. The microRNA-212 (miR-212) and caspase-8 (CASP8) levels were determined by quantitative reverse transcription polymerase chain reaction and western blotting. The correlation between miR-212 and CASP8 was analyzed by dual-luciferase reporter analysis. Skin wound healing in mice was assessed by measuring the wound area and gap after hematoxylin-eosin (HE) staining. RES reduced the LPS-induced reduction in viability and apoptosis in HaCaT cells. miR-212 expression was reduced by LPS and increased by exposure to RES. RES promoted cell proliferation and migration after LPS treatment by increasing miR-212 levels. CASP8 was a target of miR-212. CASP8 silencing promoted cell proliferation and migration, which was reversed by miR-212 knockdown in LPS-treated HaCaT cells. RES promoted skin wound healing in mice, which was reduced by miR-212 knockdown. Thus, RES facilitates cell proliferation and migration in LPS-treated HaCaT cells and promotes skin wound-healing in a mouse model by regulating the miR-212/CASP8 axis.

Differential Response of Lung Cancer Cells, with Various Driver Mutations, to Plant Polyphenol Resveratrol and Vitamin D Active Metabolite PRI-2191

Plant polyphenols and vitamins D exhibit chemopreventive and therapeutic anticancer effects. We first evaluated the biological effects of the plant polyphenol resveratrol (RESV) and vitamin D active metabolite PRI-2191 on lung cancer cells having different genetic backgrounds. RESV and PRI-2191 showed divergent responses depending on the genetic profile of cells. Antiproliferative activity of PRI-2191 was noticeable in EGFRmut cells, while RESV showed the highest antiproliferative and caspase-3-inducing activity in KRASmut cells. RESV upregulated p53 expression in wtp53 cells, while downregulated it in mutp53 cells with simultaneous upregulation of p21 expression in both cases. The effect of PRI-2191 on the induction of CYP24A1 expression was enhanced by RESV in two KRASmut cell lines. The effect of RESV combined with PRI-2191 on cytokine production was pronounced and modulated. RESV cooperated with PRI-2191 in regulating the expression of IL-8 in EGFRmut cells, while OPN in KRASmut cells and PD-L1 in both cell subtypes. We hypothesize that the differences in response to RESV and PRI-2191 between EGFRmut and KRASmut cell lines result from the differences in epigenetic modifications since both cell subtypes are associated with the divergent smoking history that can induce epigenetic alterations.

The Effects of Aronia melanocarpa Juice Consumption on the mRNA Expression Profile in Peripheral Blood Mononuclear Cells in Subjects at Cardiovascular Risk

Foods and food products that contain polyphenols are proposed to modulate risk of cardiovascular disease. The aim of this three-arm, crossover, randomized, double-blind, placebo-controlled intervention study was to examine the impact of Aronia melanocarpa juice (AMJ), high-polyphenol (AMJ treatment, 1.17 g/100 mL polyphenols) and low-polyphenol (dAMJ treatment, 0.29 g/100 mL polyphenols) dose, on the transcriptome in peripheral blood mononuclear cells (PBMC) of 19 subjects at cardiovascular risk. Transcriptome data were obtained by microarray. Bioinformatic functional annotation analysis was performed on both the whole transcriptome datasets and the differentially expressed genes (DEGs). Expression of selected DEGs was validated by RT-qPCR. Administration of AMJ and dAMJ treatments during the two consecutive four-week treatment periods had additive effects on PBMC transcriptome profiles, with the most pronounced and specific effect noticed for AMJ in the last treatment period (TP3) of the trial. Between the high-dose and low-dose treatments in TP3, there was a multitude of overlapping DEGs and DEG-enriched biological processes and pathways, which primarily included immunomodulation and regulation of cell proliferation/death. Increased expression of TNF, IL1B, IL8, RGS1, OSM, and DUSP2 in TP3 was confirmed by RT-qPCR. The results suggest the immunomodulatory effects of prolonged habitual consumption of polyphenol-rich aronia juice in individuals at cardiovascular risk.

Role of Resveratrol in Regulating Cutaneous Functions

Protective role of the skin is against external insults and maintenance of electrolyte homeostasis of the body. Cutaneous dysfunction can account for the development of both cutaneous and systemic disorders. Thus, improvements in cutaneous functions can benefit a number of extracutaneous and cutaneous functions. Resveratrol, a natural ingredient, displays multiple benefits for various systems/organs, including the skin. The benefits of resveratrol for cutaneous functions include stimulation of keratinocyte differentiation and antimicrobial peptide expression, inhibition of keratinocyte proliferation and cutaneous inflammation, UV protection, anticancer, antiaging, and inhibition of melanogenesis. The mechanisms of action of resveratrol include activation of sirtuin 1 and nuclear factor erythroid 2-related factor 2, and inhibition of mitogen-activated protein kinase signaling. Evidence suggests that topical resveratrol could be a valuable alternative not only for daily skin care, but also for the prevention and treatment of various cutaneous disorders. This review summarizes the benefits of resveratrol for cutaneous functions.

Agro-Industrial By-Products and Their Bioactive Compounds—An Ally against Oxidative Stress and Skin Aging

The increased consumer awareness towards hazards related with sun exposure has given a boost in the cosmetics industry and particularly the sun care market. Human skin is continually being threatened by the UV irradiation present in sunlight and acute UV exposure leads to skin photoaging. Cosmetic and/or dermatological applications include several bioactive compounds that contribute to the regulation of epidermal homeostasis by providing protection against solar radiation and improving the antioxidant activity of epidermis. Plant extracts are sources of active ingredients with intense therapeutic properties, and the topical application or oral intake of these compounds could ameliorate skin condition. Nowadays, there is a growing demand for the application of the bioactive agents contained in agro-industrial byproducts in sun care products, since many of them have shown promising properties as skin photoprotectants. However, well-conducted clinical studies are required to prove their safety and efficacy before they could be regularly used. Environmentally friendly extraction and sustainable techniques are therefore under examination for recovering such compounds from agro-industrial byproducts and converting them into innovative high-value natural ingredients used in cosmetic formulations.

Transcriptome-Based Analysis in Lactobacillus plantarum WCFS1 Reveals New Insights into Resveratrol Effects at System Level

SCOPE

This study was undertaken to expand our insights into the mechanisms involved in the tolerance to resveratrol (RSV) that operate at system-level in gut microorganisms and advance knowledge on new RSV-responsive gene circuits.

METHODS AND RESULTS

Whole genome transcriptional profiling was used to characterize the molecular response of Lactobacillus plantarum WCFS1 to RSV. DNA repair mechanisms were induced by RSV and responses were triggered to decrease the load of copper, a metal required for RSV-mediated DNA cleavage, and H₂ S, a genotoxic gas. To counter the effects of RSV, L. plantarum strongly up- or downregulated efflux systems and ABC transporters pointing to transport control of RSV across the membrane as a key mechanism for RSV tolerance. L. plantarum also downregulated tRNAs, induced chaperones, and reprogrammed its transcriptome to tightly control ammonia levels. RSV induced a probiotic effector gene and a likely deoxycholate transporter, two functions that improve the host health status.

CONCLUSION

Our data identify novel protective mechanisms involved in RSV tolerance operating at system level in a gut microbe. These insights could influence the way RSV is used for a better management of gut microbial ecosystems to obtain associated health benefits.

Natural Substances for Prevention of Skin Photoaging: Screening Systems in the Development of Sunscreen and Rejuvenation Cosmetics

Solar broadband UV irradiation is commonly regarded as a major causative reason for cutaneous photoaging. The pro-aging molecular pathways and cellular targets affected by UVA+UVB light in human skin have been extensively investigated. Notwithstanding growing knowledge in mechanisms of photoaging, research and development of clinically efficient, nontoxic, and sustainable topical preparations providing full physical, chemical, and biological photoprotection still remain a great challenge for pharmaceutical and cosmetic industries. In this study, we are proposing a panel of the in vitro methods for preselection of natural photoprotective substances with high photostability and low phototoxicity able of absorbing a broadband UVA+UVB irradiation (physical sunscreen), reducing UV-related overproduction of free radicals and loss of endogenous antioxidants (chemical protection), and attenuating UV-induced cytotoxicity and immune and metabolic responses (biological protection) in primary human epidermal keratinocytes and immortalized human keratinocyte cultures. Our data showed that secondary metabolites biosynthesized in plant cells in response to UV irradiation, such as phenylpropanoids and their glycosylated metabolites, aglycons and glycosylated flavonoids, and leontopodic acids, hold the best promise for complete natural topical prevention of photoaging and rejuvenation of photoaged skin. Meristem plant cell cultures elicited by solar simulating UV could be the most environmentally sustainable biotechnological source of polyphenols with combined photoprotective and antiaging properties.

Convergent Effects of Resveratrol and PYK2 on Prostate Cells

Resveratrol, a dietary polyphenol, is under consideration as chemopreventive and chemotherapeutic agent for several diseases, including cancer. However, its mechanisms of action and its effects on non-tumor cells, fundamental to understand its real efficacy as chemopreventive agent, remain largely unknown. Proline-rich tyrosine kinase 2 (PYK2), a non-receptor tyrosine kinase acting as signaling mediator of different stimuli, behaves as tumor-suppressor in prostate. Since, PYK2 and RSV share several fields of interaction, including oxidative stress, we have investigated their functional relationship in human non-transformed prostate EPN cells and in their tumor-prone counterpart EPN-PKM, expressing a PYK2 dead-kinase mutant. We show that RSV has a strong biological activity in both cell lines, decreasing ROS production, inducing morphological changes and reversible growth arrest, and activating autophagy but not apoptosis. Interestingly, the PYK2 mutant increases basal ROS and autophagy levels, and modulates the intensity of RSV effects. In particular, the anti-oxidant effect of RSV is more potent in EPN than in EPN-PKM, whereas its anti-proliferative and pro-autophagic effects are more significant in EPN-PKM. Consistently, PYK2 depletion by RNAi replicates the effects of the PKM mutant. Taken together, our results reveal that PYK2 and RSV act on common cellular pathways and suggest that RSV effects on prostate cells may depend on mutational-state or expression levels of PYK2 that emerges as a possible mediator of RSV mechanisms of action. Moreover, the observation that resveratrol effects are reversible and not associated to apoptosis in tumor-prone EPN-PKM cells suggests caution for its use in humans.

Effects of Resveratrol on p66Shc phosphorylation in cultured prostate cells

There is increasing evidence that diet plays a crucial role in age-related diseases and cancer. Oxidative stress is a conceivable link between diet and diseases, thus food antioxidants, counteracting the damage caused by oxidation, are potential tools for fight age-related diseases and cancer. Resveratrol (RSV), a polyphenolic antioxidant from grapes, has gained enormous attention particularly because of its ability to induce growth arrest and apoptosis in cancer cells, and it has been proposed as both chemopreventive and therapeutic agent for cancer and other diseases. Even though the effects of RSV have been studied in prostate cancer cells and animal models, little is known about its effects on normal cells and tissues. To address this issue, we have investigated the effects of RSV on EPN cells, a human non-transformed prostate cell line, focusing on the relationship between RSV and p66Shc, a redox enzyme whose activities strikingly intersect those of RSV. p66Shc activity is regulated by phosphorylation of serine 36 (Ser36) and has been related to mitochondrial oxidative stress, apoptosis induction, regulation of cell proliferation and migration. Here we show that RSV inhibits adhesion, proliferation and migration of EPN cells, and that these effects are associated to induction of dose- and time-dependent p66Shc-Ser36 phosphorylation and ERK1/2 de-phosphorylation. Moreover, we found that RSV is able to activate also p52Shc, another member of the Shc protein family. These data show that RSV affects non-transformed prostate epithelial cells and suggest that Shc proteins may be key contributors of RSV effects on prostate cells.

Effect of mercury on porcine ovarian granulosa cells in vitro

The objective of this in vitro study was to examine dose-dependent changes in the secretion activity [progesterone (P4) and insulin-like growth factor-I (IGF-I)] of porcine ovarian granulosa cells after experimental mercury (Hg) administration, including its apoptotic potential so as to ascertain the possible involvement of Hg in steroidogenesis. Ovarian granulosa cells were incubated with mercuric chloride [mercury (II) chloride or HgCl2] at the doses 50-250 μg mL(-1) for 18 h and compared with control group without Hg addition. Release of P4 and IGF-I by ovarian granulosa cells was assessed by RIA and apoptosis by TUNEL assay. Observations show that P4 release by granulosa cells was significantly (P < 0.05) inhibited at all the doses, while IGF-I release was not affected at any of the doses used, although a decreasing trend in the release of IGF-I was noted in comparison to control. An increasing trend of apoptosis of granulosa cells was noted, the difference being significant (P < 0.05) only at the dose 130 μg mL(-1) HgCl2, in comparison to control. Obtained data suggest a direct effect of Hg on the release of steroid hormone progesterone but not growth factor IGF-I, and a dose-dependent effect on apoptosis of porcine ovarian granulosa cells. Results indicate the interference of Hg in the pathways of steroidogenesis and apoptosis of porcine ovarian granulosa cells.

Evaluation of characteristics and in vitro antioxidant properties of RSV loaded hyaluronic acid-DPPC microparticles as a wound healing system

Resveratrol (RSV) was incorporated into microparticles by spray drying to treat chronic wounds such as diabetic ulcers. RSV was chosen due to its defense mechanisms as the formation of free radicals delays the healing process. RSV was loaded into microparticles consisting of dipalmitoylphosphatidylcholine (DPPC) and hyaluronic acid (HA), a polysaccharide naturally present within the skin, known to contribute to the healing process. Microparticles were evaluated in terms of production yield, size distribution, encapsulation efficiency, morphology, specific surface area, thermal properties and water content. Spherical and homogenous microparticles (span ≤ 2) in a size range between 20 and 30 μm were obtained with high encapsulation efficiency (≥ 97%). The effect of enzymes (hyaluronidase, phospholipase and lipase) on RSV release showed a dose-dependent pattern followed by a slow release stage. Cytotoxicity/proliferation and oxidative stress parameters (glutathione, oxidized glutathione, glutathione peroxidase, malondialdehyde, superoxide dismutase) obtained from human dermal fibroblast cell cultures revealed that formulations increased cell proliferation and the presence of RSV decreased oxidation in cells. RSV-loaded HA-DPPC microparticles appear as a promising formulation for wound healing due to synergistic effect of the ingredients.

Verbascoside--a review of its occurrence, (bio)synthesis and pharmacological significance

Phenylethanoid glycosides are naturally occurring water-soluble compounds with remarkable biological properties that are widely distributed in the plant kingdom. Verbascoside is a phenylethanoid glycoside that was first isolated from mullein but is also found in several other plant species. It has also been produced by in vitro plant culture systems, including genetically transformed roots (so-called 'hairy roots'). Verbascoside is hydrophilic in nature and possesses pharmacologically beneficial activities for human health, including antioxidant, anti-inflammatory and antineoplastic properties in addition to numerous wound-healing and neuroprotective properties. Recent advances with regard to the distribution, (bio)synthesis and bioproduction of verbascoside are summarised in this review. We also discuss its prominent pharmacological properties and outline future perspectives for its potential application.

A Huge PVDF Adsorption Difference Between Resveratrol and ε-Viniferin Allows to Quantitatively Purify Them and to Assess Their Anti-Tyrosinase Property

Repeated chromatographic analyses of polyphenolic vine stalks extracts allowed us to note a huge adsorption difference on polyvinylidene fluoride (PVDF), between trans-resveratrol 1 and (+)-trans-ε-viniferin 2. We could optimize the conditions (solvent, saturation of the process), for this polymer to adsorb very selectively 2, with regard to the monomer 1 that remains in solution. Since membrane filters made of PVDF are quite often used for HPLC samples filtration, this observation prompted us to inform phytochemists studying plant stilbenoid contents. Based on this background information, we developed a straightforward and inexpensive enrichment process for either 1 and/or 2, from crude Vitis vinifera stalks extracts, allowing to get them in a pure form. Having at hand large amounts of these two pure compounds, they were tested and compared to a set of other relevant molecules for some biological properties: trans-ε-viniferin 2 was shown to be the most powerful tyrosinase inhibitor, among all samples tested.

Active ingredients against human epidermal aging

The decisive role of the epidermis in maintaining body homeostasis prompted studies to evaluate the changes in epidermal structure and functionality over the lifetime. This development, along with the identification of molecular mechanisms of epidermal signaling, maintenance, and differentiation, points to a need for new therapeutic alternatives to treat and prevent skin aging. In addition to recovering age- and sun-compromised functions, proper treatment of the epidermis has important esthetic implications. This study reviews active ingredients capable of counteracting symptoms of epidermal aging, organized according to the regulation of specific age-affected epidermal functions: (1) several compounds, other than retinoids and derivatives, act on the proliferation and differentiation of keratinocytes, supporting the protective barrier against mechanical and chemical insults; (2) natural lipidic compounds, as well as glycerol and urea, are described as agents for maintaining water-ion balance; (3) regulation of immunological pathogen defense can be reinforced by natural extracts and compounds, such as resveratrol; and (4) antioxidant exogenous sources enriched with flavonoids and vitamin C, for example, improve solar radiation protection and epidermal antioxidant activity. The main objective is to provide a functional classification of active ingredients as regulatory elements of epidermal homeostasis, with potential cosmetic and/or dermatological applications.

Cobalt-induced hormonal and intracellular alterations in rat ovarian fragments in vitro

The objective of this in vitro study was to examine dose-dependent changes in the secretion activity (progesterone, 17β-estradiol and insulin-like growth factor-I) of rat ovarian fragments after experimental cobalt (Co) administration including the apoptotic potential of Co on rat ovarian fragments by evaluating the expression of apoptotic markers Bax and caspase-3. Ovarian fragments were incubated with cobalt sulphate (CoSO4.7H2O) at the doses 90, 170, 330 and 500 μg.mL(-1) for 24 h and compared with control group without Co addition. Release of progesterone (P4) 17β-estradiol and insulin-like growth factor-I (IGF-I) by ovarian fragments was assessed by RIA, expression of Bax and caspase-3 by SDS-PAGE and Western blotting. Observations show that P4 release by ovarian fragments was significantly (P < 0.05) inhibited after cobalt sulphate addition at higher doses 170-500 μg.mL(-1) used in the study in comparison to control. However, cobalt sulphate addition did not cause any significant change in the release of 17β-estradiol by ovarian fragments at all the doses used in the study (90-500 μg.mL(-1)) in comparison to control. On the contrary, IGF-I release by ovarian fragments was significantly (P < 0.05) stimulated after cobalt sulphate addition at the lowest dose 90 μg.mL(-1) in comparison to control, while other doses did not cause any significant change. Also, addition of cobalt sulphate decreased the expression of both the apoptotic peptides Bax and caspase-3 at the higher doses 170, 330 and 500 μg.mL(-1), but not at the lowest dose 90 μg.mL(-1) used in the study. Obtained results suggest Co induced (1) inhibition in secretion of steroid hormone progesterone, (2) dose-dependent increase in the release of growth factor IGF-I, and (3) decrease in the expression of markers of apoptosis (Bax and caspase-3) of rat ovarian fragments.