Effects of isocamptothecin, a novel camptothecin analogue, on proliferation, apoptosis and telomerase activity in HaCaT cells

A Route for Investigating Psoriasis: From the Perspective of the Pathological Mechanisms and Therapeutic Strategies of Cancer

Psoriasis is an incurable skin disease that develops in about two-thirds of patients before the age of 40 and requires lifelong treatment; its pathological mechanisms have not been fully elucidated. The core pathological process of psoriasis is epidermal thickening caused by the excessive proliferation of epidermal keratinocytes, which is similar to the key feature of cancer; the malignant proliferation of cancer cells causes tumor enlargement, suggesting that there is a certain degree of commonality between psoriasis and cancer. This article reviews the pathological mechanisms that are common to psoriasis and cancer, including the interaction between cell proliferation and an abnormal immune microenvironment, metabolic reprogramming, and epigenetic reprogramming. In addition, there are common therapeutic agents and drug targets between psoriasis and cancer. Thus, psoriasis and cancer share a common pathological mechanisms-drug targets-therapeutic agents framework. On this basis, it is proposed that investigating psoriasis from a cancer perspective is beneficial to enriching the research strategies related to psoriasis.

Advances in the Application of Natural Products and the Novel Drug Delivery Systems for Psoriasis

Psoriasis, an incurable autoimmune skin disease, is one of the most common immune-mediated disorders. Presently, numerous clinical research studies are underway, and treatment options are available. However, these treatments focus on improving symptoms of the disease and fail to achieve a radical cure; they also have certain toxic side effects. In recent years, natural products have increasingly gained attention because of their high efficiency and low toxicity. Despite their obvious therapeutic effects, natural products’ biological activity was limited by their instability, poor solubility, and low bioavailability. Novel drug delivery systems, including liposomes, lipospheres, nanostructured lipid carriers, niosomes, nanoemulsions, nanospheres, microneedles, ethosomes, nanocrystals, and foams could potentially overcome the limitations of poor water solubility and permeability in traditional drug delivery systems. Thus, to achieve a therapeutic effect, the drug can reach the epidermis and dermis in psoriatic lesions to interact with the immune cells and cytokines.

Treatment Strategies Against Psoriasis: Principle, Perspectives and Practices

BACKGROUND

Psoriasis is a genetically predisposed autoimmune disease mediated by cytokines released by the activated immune cells. It manifests inflammatory, scaly red or white silvery flaky skin which may be a fluid-filled lesion with soreness and itchiness. The prevalence rate of psoriasis is increasing day by day. Despite having such a high prevalence rate, the treatment of psoriasis is still limited. Hence, there is a need to rethink the various treatment strategies available in the allopathic as well as in the alternative systems of medicine.

METHODS

Various bibliographic databases of previously published peer-reviewed research papers were explored and systematic data culminated in terms of various treatment strategies used for the management of psoriasis. The prime focus is given towards modern as well as alternative systems of medicine such as phototherapy, a combination of phototherapy with pharmacotherapy such as Ayurveda, Yoga and naturopathy, Unani, Siddha, and Homeopathy to treat psoriasis.

RESULTS

A comprehensive review of 161 papers, including both research and review articles, was carried out to make the article readily understandable. The pathogenesis including inflammatory mediators and type of psoriasis is discussed before the treatment strategies to understand the pathophysiology of the disease. The uniqueness, procedure, advantages, and limitations of conventional, advanced, and traditional systems of medicine to treat psoriasis are discussed in detail. Emphasis has also been given towards marine sources such as fish oil, marine sponges, and algae.

CONCLUSION

Although there are many modern and alternative treatment strategies available to treat psoriasis, none of them have been proven to provide complete relief to patients. Moreover, they are associated with certain side effects. In order to overcome them, novel drug delivery systems have been utilized and found effective; however, their stability and safety become the major impediments towards their successful positioning. Traditional and alternative treatment strategies have found to be safe and effective but their use is localized to certain areas. In a nutshell, to achieve successful treatment of psoriasis, there is a need to focus on the development of stable and non-toxic novel drug delivery systems or the promotion of traditional systems to treat psoriasis.

18β-Glycyrrhetinic acid induces human HaCaT keratinocytes apoptosis through ROS-mediated PI3K-Akt signaling pathway and ameliorates IMQ-induced psoriasis-like skin lesions in mice

Background

Psoriasis is a chronic inflammatory skin disease affecting 2–3% of the population worldwide. Hyperproliferative keratinocytes were thought to be an amplifier of inflammatory response, thereby sustaining persistence of psoriasis lesions. Agents with the ability to inhibit keratinocyte proliferation or induce apoptosis are potentially useful for psoriasis treatment. 18β-Glycyrrhetinic acid (GA), an active metabolite of glycyrrhizin, exhibits diverse pharmacological activities, including anti-inflammatory, anti-bacteria and anti-proliferation. The current study aims to evaluate the effects of GA on the proliferation and apoptosis of human HaCaT keratinocytes in vitro and investigate the effects of GA on the skin lesions of imiquimod (IMQ)-induced psoriasis-like mouse model in vivo.

Methods

Cell viability was assayed by CCK-8. Flow cytometry was performed to measure apoptosis and reactive oxygen species (ROS), with Annexin V-FITC/PI detection kit and DCFH-DA probe respectively. Caspase 9/3 activities were measured using caspase activity assay kits. The protein levels of Akt and p-Akt were determined using Western blotting. IMQ was applied to induce psoriasis-like skin lesions in mice. The histological change in mouse skin lesions was detected using hematoxylin and eosin (H&E) staining. The severity of skin lesions was scored based on Psoriasis Area Severity Index (PASI). RT-PCR was employed to examine the relative expression of TNF-α, IL-22 and IL-17A in mouse skin lesions.

Results

GA decreased HaCaT keratinocytes viability and induced cell apoptosis in a dose-dependent manner. In the presence of GA, intracellular ROS levels were significantly elevated. NAC, a ROS inhibitor, attenuated GA-mediated HaCaT keratinocytes growth inhibition and apoptosis. In addition, GA treatment remarkably decreased p-Akt protein level, which could be restored partially when cells were co-treated with GA and NAC. LY294002 (a PI3K inhibitor) treatment significantly enhanced GA-mediated cytotoxicity. Moreover, GA ameliorated IMQ-induced psoriasis-like skin lesions in mice.

Conclusions

GA inhibits proliferation and induces apoptosis in HaCaT keratinocytes through ROS-mediated inhibition of PI3K-Akt signaling pathway, and ameliorates IMQ-induced psoriasis-like skin lesions in mice.

Effect of Topical Application of Black Seed Oil on Imiquimod-Induced Psoriasis-like Lesions in the Thin Skin of Adult Male Albino Rats

Psoriasis is a chronic inflammatory skin disease that affects about 1%-3% of the world's population. Black seed oil, i.e., the oil extracted from black seeds (Nigella sativa seeds), possesses a broad spectrum of pharmacological actions including anti-inflammatory, immunostimulatory, and antioxidant properties. This study aimed to investigate the effect of black seed oil on imiquimod (IMQ) induced psoriasis-like skin lesions. To this end, 30 male albino rats were divided into three groups: group I, control group; group II, psoriasis-induced group receiving daily topical applications of IMQ cream (5%) on the shaved back skin for 10 consecutive days; and group III, black seed oil group receiving a daily topical dose of black seed oil 5 mg/kg body weight for 10 days after induction of psoriasis. Animals of all groups were sacrificed and specimens obtained from the skin of the central part of the back were processed for histological and immunohistochemical staining with proliferating cell nuclear antigen (PCNA). IMQ application led to epidermal inflammation, hyperplasia and alterations in the normal appearance of keratinocytes with degenerative changes observed at both light and electron microscopic levels. Collagenous fibers were abundant in the dermis and PCNA-positive cells were detected in all layers of the epidermis. However, topical use of black seed oil strongly inhibited IMQ-induced psoriasis-like inflammation and alleviated all epidermal and dermal changes observed after IMQ application, allowing us to conclude that black seed oil can be used as an adjuvant topical therapy for treating psoriasis. Anat Rec, 2017. © 2017 Wiley Periodicals, Inc. Anat Rec, 301:166-174, 2018. © 2017 Wiley Periodicals, Inc.

Zanthoxylum bungeanum essential oil induces apoptosis of HaCaT human keratinocytes

ETHNOPHARMACOLOGICAL RELEVANCE

Zanthoxylum bungeanum (ZB), a Chinese herb medicine, has been shown to possess a wide range of biological activities including anti-tumor, anti-inflammatory, and anti-microbial activity and has long been used to treat a variety of skin diseases including psoriasis. However, the underlying mechanism of action has not been systematically elucidated.

AIM OF THE STUDY

to analyze the chemical composition of the hydro-distilled Zanthoxylum bungeanum essential oil (ZBEO), and to investigate its anti-proliferative activity on HaCaT cells as well as the underlying anti-psoriasis mechanisms.

MATERIALS AND METHODS

The chemical composition of ZBEO was analyzed with gas chromatography coupled to mass spectrometry (GC-MS). HaCaT cells was exposed to different dose of ZBEO added in medium prior to morphologic features analysis as well as cell cycle arrest examination with Flow cytometry. Western blot analysis was employed to estimate the expression level of proteins including caspase-8/9/3, PARP, Bax and Bcl-2.

RESULTS

Thirty-nine compounds of the ZBEO were identified GC-MS. ZBEO-treated HaCaT cells showed typical apoptotic morphologic features by DAPI staining assay. The ZBEO significantly inhibited proliferation of HaCaT cells in a dose- and time-dependent manner and induced S phase arrest apoptosis in HaCaT cells. Furthermore, western blot analysis revealed that the ZBEO increased expression of cleaved caspase-8/9/3, PARP, and Bax, decreased Bcl-2 levels.

CONCLUSION

ZBEO inhibits the proliferation of HaCaT cells, resulting from the induction of cellular apoptosis through both intrinsic and extrinsic pathways. ZBEO is a potential candidate that may be considered for development into an anti-psoriasis drug.

How Phytochemicals Prevent Chemical Carcinogens and/or Suppress Tumor Growth?

Phytochemicals are a powerful group of chemicals that are derived from natural resource, especially with plants origin. They have shown to exhibit chemoprevention and chemotherapeutic effects not only in cell lines and in animal models of cancer but also some of them are in the clinical trial phase I and II. Despite numerous reports of these phytochemical effects on cancer, an overview of the mechanisms of their action and their effects on various cellular and molecular functions important in the inhibition of cancer progression has been lacking. In this review, we attempt to catalogue various studies to examine the effect of phytochemicals in cancer initiation, promotion, signaling, and epigenetic changes. Because of the numerous studies in these topics, we only pointed out to some examples in each section.

Perspectives on biologically active camptothecin derivatives

Camptothecins (CPTs) are cytotoxic natural alkaloids that specifically target DNA topoisomerase I. Research on CPTs has undergone a significant evolution from the initial discovery of CPT in the late 1960s through the study of synthetic small-molecule derivatives to investigation of macromolecular constructs and formulations. Over the past years, intensive medicinal chemistry efforts have generated numerous CPT derivatives. Three derivatives, topotecan, irinotecan, and belotecan, are currently prescribed as anticancer drugs, and several related compounds are now in clinical trials. Interest in other biological effects, besides anticancer activity, of CPTs is also growing exponentially, as indicated by the large number of publications on the subject during the last decades. Therefore, the main focus of the present review is to provide an ample but condensed overview on various biological activities of CPT derivatives, in addition to continued up-to-date coverage of anticancer effects.

Poly(amido amine) dendrimers as absorption enhancers for oral delivery of camptothecin

Oral delivery of camptothecin has a treatment advantage but is limited by low bioavailability and gastrointestinal toxicity. Poly(amido amine) or PAMAM dendrimers have shown promise as intestinal penetration enhancers, drug solubilizers and drug carriers for oral delivery in vitro and in situ. There have been very limited studies in vivo to evaluate PAMAM dendrimers for oral drug delivery. In this study, camptothecin (5 mg/kg) was formulated and co-delivered with cationic, amine-terminated PAMAM dendrimer generation 4.0 (G4.0) (100 and 300 mg/kg) and anionic, carboxylate-terminated PAMAM generation 3.5 (G3.5) (300 and 1000 mg/kg) in CD-1 mice. Camptothecin associated to a higher extent with G4.0 than G3.5 in the formulation, attributed to an electrostatic interaction on the surface of G4.0. Both PAMAM G4.0 and G3.5 increased camptothecin solubilization in simulated gastric fluid and caused a 2-3 fold increase in oral absorption of camptothecin when delivered at 2 h. PAMAM G4.0 and G3.5 did not increase mannitol transport suggesting that the oral absorption of camptothecin was not due to tight junction modulation. Histologic observations of the epithelial layer of small intestinal segments of the gastrointestinal tract (GIT) at 4 h post dosing supported no evidence of toxicity at the evaluated doses of PAMAM dendrimers. This study demonstrates that both cationic (G.4) and anionic (G3.5) PAMAM dendrimers were effective in enhancing the oral absorption of camptothecin. Results suggest that drug inclusion in PAMAM interior controlled solubilization in simulated gastric and intestinal fluids, and increased oral bioavailability.

1,4-dihydroxy-2-naphthoic Acid Induces Apoptosis in Human Keratinocyte: Potential Application for Psoriasis Treatment

Psoriasis, which affects approximately 1–3% of the population worldwide, is a chronic inflammatory skin disorder characterized by epidermal keratinocytes hyperproliferation, abnormal differentiation, and inflammatory infiltration. Decrease in keratinocyte apoptosis is a specific pathogenic phenomenon in psoriasis. Chinese herbs have been used for the treatment of psoriasis in China showing promising effect in clinical trials. A traditional Chinese medicine has relatively fewer side effects with longer remission time and lower recurrence rate. The extract of Rubia cordifolia L. (EA) was previously found by us to induce HaCaT keratinocytes apoptosis. In this study we identified one of the components in Rubia cordifolia L., the anthraquinone precursor 1,4-dihydroxy-2-naphthoic acid (DHNA), induces HaCaT keratinocytes apoptosis through G0/G1 cell cycle arrest. We have also demonstrated that DHNA acts through both caspase-dependent and caspase-independent pathways. Besides, cytotoxicity and IL-1α release assays indicate that DHNA causes less irritation problems than dithranol, which is commonly employed to treat psoriasis in many countries. Since DHNA possesses similar apoptotic effects on keratinocytes as dithranol but causes less irritation, DHNA therefore constitutes a promising alternative agent for treating psoriasis. Our studies also provide an insight on the potential of using EA and DHNA, alternatively, as a safe and effective treatment modality for psoriasis.

Plants and plant products with potential antipsoriatic activity--a review

CONTEXT

Psoriasis vulgaris is a hyper proliferative, autoimmune skin disorder affecting 1-3% of the world's population. The prescribed synthetic drugs for the treatment of psoriasis are associated with severe side effects, thus, researchers around the globe are searching for new, effective, and safer drugs from natural resources.

OBJECTIVE

The present review has been prepared with an objective to compile exhaustive literature on pharmacological reports on antipsoriatic plants, plant products, and formulations. An attempt has been made to incorporate chemical constituents (with structures) isolated from different plants responsible for antipsoriatic activity and their possible mechanism of actions in this review.

MATERIALS AND METHODS

The review has been compiled using references from major databases like Chemical Abstracts, Medicinal and Aromatic Plants Abstracts, PubMed, Scirus, Google scholar, Open J Gate, Scopus, Science Direct and Online Journals, and includes 127 references.

RESULTS

A survey of literature revealed that extracts/fractions/isolates from 18 plants, 23 chemical constituents of plant origin and 40 plant-based formulations from various systems of medicine have been reported to possess antipsoriatic activity, and 37 antipsoriatic formulations containing plants have been patented.

CONCLUSION

Preliminary antipsoriatic activity studies have been carried out on crude extracts of traditionally used and medicinally promising plants. Such plants need to be explored properly with a view to isolate antipsoriatic constituents, and to evaluate their possible mode of actions so that these plant drugs could be exploited properly as potential antipsoriatic drugs.

Death ligand TRAIL, secreted by CD1a+ and CD14+ cells in blister fluids, is involved in killing keratinocytes in toxic epidermal necrolysis

Toxic epidermal necrolysis (TEN) is characterized by an acute detachment and destruction of keratinocytes, affecting large areas of the skin. It is often related to adverse drug reactions. Previous studies have shown that effector CD8+ T cells, which accumulate in the blister fluid, are functionally cytotoxic and act through a classical perforin/granzyme B pathway. It has recently been shown that these cytotoxic T cells also secrete granulysin peptide, which is lethal to keratinocytes. These cytotoxic T cells exert their killer activity against autologous keratinocytes in the presence of the drug. However, they are unlikely to be the only effectors of TEN. We therefore searched for soluble death factors in the blister fluids that might kill keratinocytes. We found that the amounts of interferon-γ, TRAIL and TNF-α proteins were significantly greater in TEN blister fluids than in all controls (normal sera, TEN sera, burns and Eosinophilic pustular folliculitis blister fluids) and TNF-like weak inducer of apoptosis (TWEAK) amounts are also greater in all controls except burns. We showed that these proteins acted in synergy to induce the death of keratinocytes in vitro. We also found that TRAIL and TWEAK were secreted by CD1a+ and CD14+ cells present in the blister fluids. Thus, in addition to MHC class I-restricted cytotoxic T lymphocytes (CTLs), which lyse keratinocytes, ligands secreted by non-lymphoid cells capable of inducing keratinocyte death in an MHC class I-independent manner, also seem to be present in the blister fluids of patients with TEN.