RNA-Based Antipsoriatic Gene Therapy: An Updated Review Focusing on Evidence from Animal Models

Psoriasis presents as a complex genetic skin disorder, characterized by the interaction between infiltrated immune cells and keratinocytes. Substantial progress has been made in understanding the molecular mechanisms of both coding and non-coding genes, which has positively impacted clinical treatment approaches. Despite extensive research into the genetic aspects of psoriasis pathogenesis, fully grasping its epigenetic component remains a challenging endeavor. In response to the pressing demand for innovative treatments to alleviate inflammatory skin disorders, various novel strategies are under consideration. These include gene therapy employing antisense nucleotides, silencing RNA complexes, stem cell therapy, and antibody-based therapy. There is a pressing requirement for a psoriasis-like animal model that replicates human psoriasis to facilitate early preclinical evaluations of these novel treatments. The authors conduct a comprehensive review of various gene therapy in different psoriasis-like animal models utilized in psoriasis research. The animals included in the list underwent skin treatments such as imiquimod application, as well as genetic and biologic injections, and the results of these interventions are detailed. Animal models play a crucial role in translating drug discoveries from the laboratory to clinical practice, and these models aid in improving the reproducibility and clinical applicability of preclinical data. Numerous animal models with characteristics similar to those of human psoriasis have proven to be useful in understanding the development of psoriasis. In this review, the article focuses on RNA-based gene therapy exploration in different types of psoriasis-like animal models to improve the treatment of psoriasis.

Chemo-photothermal therapy of chitosan/gold nanorod clusters for antibacterial treatment against the infection of planktonic and biofilm MRSA

Bacterial infections trigger inflammation and impede the closure of skin wounds. The misuse of antibiotics exacerbates skin infections by generating multidrug-resistant bacteria. In this study, we developed chemo-photothermal therapy (chemo-PTT) based on near-infrared (NIR)-irradiated chitosan/gold nanorod (GNR) clusters as anti-methicillin-resistant Staphylococcus aureus (MRSA) agents. The nanocomposites exhibited an average size of 223 nm with a surface charge of 36 mV. These plasmonic nanocomposites demonstrated on-demand and rapid hyperthermal action under NIR. The combined effect of positive charge and PTT by NIR-irradiated nanocomposites resulted in a remarkable inhibition rate of 96 % against planktonic MRSA, indicating a synergistic activity compared to chitosan nanoparticles or GNR alone. The nanocomposites easily penetrated the biofilm matrix. The combination of chemical and photothermal treatments by NIR-stimulated clusters significantly damaged the biofilm structure, eradicating MRSA inside the biomass. NIR-irradiated chitosan/GNR clusters increased the skin temperature of mice by 13 °C. The plasmonic nanocomposites induced negligible skin irritation in vivo. In summary, this novel nanosystem demonstrated potent antibacterial effects against planktonic and biofilm MRSA, showcasing the possible efficacy in treating skin infections.

Development of nanoparticles incorporated with quercetin and ACE2-membrane as a novel therapy for COVID-19

INTRODUCTION

Angiotensin-converting enzyme 2 (ACE2) and AXL tyrosine kinase receptor are known to be involved in the SARS-CoV-2 entry of the host cell. Therefore, targeting ACE2 and AXL should be an effective strategy to inhibit virus entry into cells. However, developing agents that can simultaneously target ACE2 and AXL remains a formidable task. The natural compound quercetin has been shown to inhibit AXL expression.

MATERIALS AND METHODS

In this study, we employed PLGA nanoparticles to prepare nanoparticles encapsulated with quercetin, coated with ACE2-containing cell membranes, or encapsulated with quercetin and then coated with ACE-2-containing cell membranes. These nanoparticles were tested for their abilities to neutralize or inhibit viral infection.

RESULTS

Our data showed that nanoparticles encapsulated with quercetin and then coated with ACE2-containing cell membrane inhibited the expression of AXL without causing cytotoxic activity. Nanoparticles incorporated with both quercetin and ACE2-containing cell membrane were found to be able to neutralize pseudo virus infection and were more effective than free quercetin and nanoparticles encapsulated with quercetin at inhibition of pseudo virus and SARS-CoV-2 infection.

CONCLUSIONS

We have shown that the biomimetic nanoparticles incorporated with both ACE-2 membrane and quercetin showed the most antiviral activity and may be further explored for clinical application.

Facile adipocyte uptake and liver/adipose tissue delivery of conjugated linoleic acid-loaded tocol nanocarriers for a synergistic anti-adipogenesis effect

Obesity is a major risk to human health. Adipogenesis is blocked by α-tocopherol and conjugated linoleic acid (CLA). However, their effect at preventing obesity is uncertain. The effectiveness of the bioactive agents is associated with their delivery method. Herein, we designed CLA-loaded tocol nanostructured lipid carriers (NLCs) for enhancing the anti-adipogenic activity of α-tocopherol and CLA. Adipogenesis inhibition by the nanocarriers was examined using an in vitro adipocyte model and an in vivo rat model fed a high fat diet (HFD). The targeting of the tocol NLCs into adipocytes and adipose tissues were also investigated. A synergistic anti-adipogenesis effect was observed for the combination of free α-tocopherol and CLA. Nanoparticles with different amounts of solid lipid were developed with an average size of 121‒151 nm. The NLCs with the smallest size (121 nm) showed greater adipocyte internalization and differentiation prevention than the larger size. The small-sized NLCs promoted CLA delivery into adipocytes by 5.5-fold as compared to free control. The nanocarriers reduced fat accumulation in adipocytes by counteracting the expression of the adipogenic transcription factors peroxisome proliferator activated receptor (PPAR)γ and CCAAT/enhancer-binding protein (C/EBP)α, and lipogenic enzymes acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS). Localized administration of CLA-loaded tocol NLCs significantly reduced body weight, total cholesterol, and liver damage indicators in obese rats. The biodistribution study demonstrated that the nanoparticles mainly accumulated in liver and adipose tissues. The NLCs decreased adipocyte hypertrophy and cytokine overexpression in the groin and epididymis to a greater degree than the combination of free α-tocopherol and CLA. In conclusion, the lipid-based nanocarriers were verified to inhibit adipogenesis in an efficient and safe way.

Acetylshikonin induces necroptosis via the RIPK1/RIPK3-dependent pathway in lung cancer

Despite advances in therapeutic strategies, lung cancer remains the leading cause of cancer-related death worldwide. Acetylshikonin is a derivative of the traditional Chinese medicine Zicao and presents a variety of anticancer properties. However, the effects of acetylshikonin on lung cancer have not been fully understood yet. This study explored the mechanisms underlying acetylshikonin-induced cell death in non-small cell lung cancer (NSCLC). Treating NSCLC cells with acetylshikonin significantly reduced cell viability, as evidenced by chromatin condensation and the appearance of cell debris. Acetylshikonin has also been shown to increase cell membrane permeability and induce cell swelling, leading to an increase in the population of necrotic cells. When investigating the mechanisms underlying acetylshikonin-induced cell death, we discovered that acetylshikonin promoted oxidative stress, decreased mitochondrial membrane potential, and promoted G2/M phase arrest in lung cancer cells. The damage to NSCLC cells induced by acetylshikonin resembled results involving alterations in the cell membrane and mitochondrial morphology. Our analysis of oxidative stress revealed that acetylshikonin induced lipid oxidation and down-regulated the expression of glutathione peroxidase 4 (GPX4), which has been associated with necroptosis. We also determined that acetylshikonin induces the phosphorylation of receptor-interacting serine/threonine-protein kinase 1 (RIPK1)/RIPK3 and mixed lineage kinase domain-like kinase (MLKL). Treatment with RIPK1 inhibitors (necrostatin-1 or 7-Cl-O-Nec-1) significantly reversed acetylshikonin-induced MLKL phosphorylation and NSCLC cell death. These results indicate that acetylshikonin activated the RIPK1/RIPK3/MLKL cascade, leading to necroptosis in NSCLC cells. Our findings indicate that acetylshikonin reduces lung cancer cells by promoting G2/M phase arrest and necroptosis.

Topically applied pH-responsive nanogels for alkyl radical-based therapy against psoriasiform hyperplasia

Phototherapy is a conventional antipsoriatic approach based on oxygen-relevant generation of oxidative stress to inhibit keratinocyte hyperproliferation. However, this therapy can be restricted due to local hypoxia in psoriatic lesions. The generation of alkyl radicals is oxygen-independent and suppresses hyperproliferation. Herein, we established alkyl radical-based therapy to treat psoriatic hyperplasia. Because alkyl radicals are short-lived compounds, we loaded 2,2'-azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride (AIPH) as a precursor of alkyl radicals into the chitosan nanogels to improve stability. The present study presented a topically applied nanogel that led to a pH-responsive network sensitive to skin pH. This pH responsiveness of the nanogels allowed fast alkyl radical release in the target site. The physicochemical properties of the prepared nanogels were determined through size, zeta potential, scanning electron microscopy, and absorption spectroscopy. The antipsoriatic activity was examined with keratinocyte- and animal-based studies. The nanogels displayed a smooth and spherical morphology with a hydrodynamic diameter of 215 nm. This size was largely increased as the environmental pH increased to 6. The nanogels heated at 44 °C produced alkyl radicals to induce keratinocyte death through the necrosis pathway. Bioimaging demonstrated that topically applied nanogels could deliver alkyl radicals into the epidermis. This targeting was accompanied by the accumulation of free radicals in the epidermis according to the 2',7'-dichlorodihydrofluorescein diacetate assay. The imiquimod-stimulated psoriasiform animal model indicated a remarkable reduction in erythema, scaling, and overexpressed cytokines upon topical treatment of the nanogels. The transepidermal water loss of the psoriasiform skin was inhibited from 51.7 to 27.0 g/m2/h, suggesting barrier function recovery by the nanocarriers. The nanogels lowered hyperplasia by decreasing the epidermal thickness from 212 to 89 μm. The incorporation of 8-hydroxypyrene-1,3,6-trisulfonic acid (HPTS) as a pH-sensitive fluorescence dye in the nanogels could be used to diagnose the severity of the psoriasiform plaque due to the stronger fluorescence of HPTS in skin with lower pH (psoriasiform skin pH = 4.4) than in healthy skin (pH = 4.9). It was possible to deliver the prepared nanogels into the epidermis to restrain hyperplasia without causing cutaneous irritation.

Tanshinone IIA suppresses burning incense-induced oxidative stress and inflammatory pathways in astrocytes

The burning incense (BI) behavior could be widely observed in Asia families. Incense sticks are often believed to be made from natural herbs and powders, and to have minimal impact on human health; however, there is limited research to support this claim. The current study aimed to identify the components of BI within the particulate matter 2.5 µm (PM_2.5) range and explore if BI has bio-toxicity effects on rat astrocytes (CTX-TNA2). The study also examined the protective effects and underlying molecular mechanisms of tanshinone IIA, a primary lipid-soluble compound found in the herb danshen (Salvia miltiorrhiza Bunge), which has been shown to benefit the central nervous system. Results showed that despite the differences in BI components compared to the atmospheric particulate matter (PM) standards, BI still had a bio-toxicity on astrocytes. BI exposure caused early and late apoptosis, reactive oxygen species (ROS) production, MAPKs (JNK, p38, and ERK), and Akt signaling activation, and inflammation-related proteins (cPLA2, COX-2, HO-1, and MMP-9) increases. Our results further exhibit that the tanshinone IIA pre-treatment could significantly avoid the BI-induced apoptosis and inflammatory signals on rat astrocytes. These findings suggest that BI exposure may cause oxidative stress in rat astrocytes and increase inflammation-related proteins and support the potential of tanshinone IIA as a candidate for preventing BI-related adverse health effects.

IOX-1 suppresses metastasis of osteosarcoma by upregulating histone H3 lysine trimethylation

New therapeutic approaches are needed for metastatic osteosarcoma (OS), as survival rates remain low despite surgery and chemotherapy. Epigenetic changes, such as histone H3 methylation, play key roles in many cancers including OS, although the underlying mechanisms are not clear. In this study, human OS tissue and OS cell lines displayed lower levels of histone H3 lysine trimethylation compared with normal bone tissue and osteoblast cells. Treating OS cells with the histone lysine demethylase inhibitor 5-carboxy-8-hydroxyquinoline (IOX-1) dose-dependently increased histone H3 methylation and inhibited cellular migratory and invasive capabilities, suppressed matrix metalloproteinase expression, reversed epithelial-to-mesenchymal transition by increasing levels of epithelial markers E-cadherin and ZO-1 and decreasing the expression of mesenchymal markers N-cadherin, vimentin, and TWIST, and also reduced stemness properties. An analysis of cultivated MG63 cisplatin-resistant (MG63-CR) cells revealed lower histone H3 lysine trimethylation levels compared with levels in MG63 cells. Exposing MG63-CR cells to IOX-1 increased histone H3 trimethylation and ATP-binding cassette transporter expression, potentially sensitizing MG63-CR cells to cisplatin. In conclusion, our study suggests that histone H3 lysine trimethylation is associated with metastatic OS and that IOX-1 or other epigenetic modulators present promising strategies to inhibit metastatic OS progression.

The role of cytokines/chemokines in an aging skin immune microenvironment

Reversing or slowing down the skin aging process is one of the most intriguing areas of focus across the social and scientific communities around the world. While aging is considered a universal and inevitable natural process of physiological decline, the aging of the skin is the most apparent visual representation of an individual's health. Aging skin may be objectively defined by epidermal thinning; increased transepidermal water loss; decreased cutaneous barrier function; loss of elasticity, laxity, and textured appearance; and gradual deterioration of the epidermal immune environment. As the largest structure of the immune system and of the body as a whole, the skin is the most vulnerable barrier of defense against the environment. The skin reflects an individual's exposures, lifestyle habits, and overall health. From an immunological perspective, cytokines and chemokines act as a central character in the communicating of the immunity in skin aging. These cell signaling proteins serve as the intercellular communication link. This review aims to elucidate how cell-cell crosstalk through cytokines and chemokines, and the interplay between host cells, infiltrating immune cells, and exogenous factors contribute to the overall aging skin.

[A prospective study on application of human umbilical cord mesenchymal stem cells combined with autologous Meek microskin transplantation in patients with extensive burns]

Objective: To investigate the effects of human umbilical cord mesenchymal stem cells (hUCMSCs) combined with autologous Meek microskin transplantation on patients with extensive burns. Methods: The prospective self-controlled study was conducted. From May 2019 to June 2022, 16 patients with extensive burns admitted to the 990th Hospital of PLA Joint Logistics Support Force met the inclusion criteria, while 3 patients were excluded according to the exclusion criteria, and 13 patients were finally selected, including 10 males and 3 females, aged 24-61 (42±13) years. A total of 20 trial areas (40 wounds, with area of 10 cm×10 cm in each wound) were selected. Two adjacent wounds in each trial area were divided into hUCMSC+gel group applied with hyaluronic acid gel containing hUCMSCs and gel only group applied with hyaluronic acid gel only according to the random number table, with 20 wounds in each group. Afterwards the wounds in two groups were transplanted with autologous Meek microskin grafts with an extension ratio of 1∶6. In 2, 3, and 4 weeks post operation, the wound healing was observed, the wound healing rate was calculated, and the wound healing time was recorded. The specimen of wound secretion was collected for microorganism culture if there was purulent secretion on the wound post operation. In 3, 6, and 12 months post operation, the scar hyperplasia in wound was assessed using the Vancouver scar scale (VSS). In 3 months post operation, the wound tissue was collected for hematoxylin-eosin (HE) staining to observe the morphological changes and for immunohistochemical staining to observe the positive expressions of Ki67 and vimentin and to count the number of positive cells. Data were statistically analyzed with paired samples t test and Bonferronni correction. Results: In 2, 3, and 4 weeks post operation, the wound healing rates in hUCMSC+gel group were (80±11)%, (84±12)%, and (92±9)%, respectively, which were significantly higher than (67±18)%, (74±21)%, and (84±16)% in gel only group (with t values of 4.01, 3.52, and 3.66, respectively, P<0.05). The wound healing time in hUCMSC+gel group was (31±11) d, which was significantly shorter than (36±13) d in gel only group (t=-3.68, P<0.05). The microbiological culture of the postoperative wound secretion specimens from the adjacent wounds in 2 groups was identical, with negative results in 4 trial areas and positive results in 16 trial areas. In 3, 6, and 12 months post operation, the VSS scores of wounds in gel only group were 7.8±1.9, 6.7±2.1, and 5.4±1.6, which were significantly higher than 6.8±1.8, 5.6±1.6, and 4.0±1.4 in hUCMSC+gel group, respectively (with t values of -4.79, -4.37, and -5.47, respectively, P<0.05). In 3 months post operation, HE staining showed an increase in epidermal layer thickness and epidermal crest in wound in hUCMSC+gel group compared with those in gel only group, and immunohistochemical staining showed a significant increase in the number of Ki67 positive cells in wound in hUCMSC+gel group compared with those in gel only group (t=4.39, P<0.05), with no statistically significant difference in the number of vimentin positive cells in wound between the 2 groups (P>0.05). Conclusions: The application of hyaluronic acid gel containing hUCMSCs to the wound is simple to perform and is therefore a preferable route. Topical application of hUCMSCs can promote healing of the autologous Meek microskin grafted area in patients with extensive burns, shorten wound healing time, and alleviate scar hyperplasia. The above effects may be related to the increased epidermal thickness and epidermal crest, and active cell proliferation.

AuAg nanocomposites suppress biofilm-induced inflammation in human osteoblasts

Staphylococcus aureus (S. aureus)forms biofilm that causes periprosthetic joint infections and osteomyelitis (OM) which are the intractable health problems in clinics. The silver-containing nanoparticles (AgNPs) are antibacterial nanomaterials with less cytotoxicity than the classic Ag compounds. Likewise, gold nanoparticles (AuNPs) have also been demonstrated as excellent nanomaterials for medical applications. Previous studies have showed that both AgNPs and AuNPs have anti-microbial or anti-inflammatory properties. We have developed a novel green chemistry that could generate the AuAg nanocomposites, through the reduction of tannic acid (TNA). The bioactivity of the nanocomposites was investigated inS. aureusbiofilm-exposed human osteoblast cells (hFOB1.19). The current synthesis method is a simple, low-cost, eco-friendly, and green chemistry approach. Our results showed that the AuAg nanocomposites were biocompatible with low cell toxicity, and did not induce cell apoptosis nor necrosis in hFOB1.19 cells. Moreover, AuAg nanocomposites could effectively inhibited the accumulation of reactive oxygen species (ROS) in mitochondria and in rest of cellular compartments after exposing to bacterial biofilm (by reducing 0.78, 0.77-fold in the cell and mitochondria, respectively). AuAg nanocomposites also suppressed ROS-triggered inflammatory protein expression via MAPKs and Akt pathways. The current data suggest that AuAg nanocomposites have the potential to be a good therapeutic agent in treating inflammation in bacteria-infected bone diseases.

Radiation-induced cancer after treatment for nasopharyngeal carcinoma: a study from a high prevalence area

BACKGROUND

Radiation-induced cancer (RIC) is a late complication in patients who have been treated for nasopharyngeal carcinoma (NPC). The comparison of index anatomic location, index histological type, and survival of RIC in patients with NPC after different radiotherapy modalities (intensity-modulated radiotherapy [IMRT], 3-dimensional conformal radiotherapy [3D-CRT], and conventional 2D radiotherapy) is currently unavailable.

METHODOLOGY

A total of 38,565 patients with NPC who received curative-intent radiotherapy at Sun Yat-sen University Cancer Center between January 1986 and December 2017 were reviewed. A total of 141 patients who developed RIC and fulfilled the study criteria were included. Categorical variables were compared by the chi-square test or Fisher's exact test. Kaplan-Meier curves were used to evaluate overall survival. Cox proportional hazards models were used to examine the independent significance of RIC treatment.

RESULTS

Among IMRT, 3D-CRT, and conventional 2D radiotherapy, the incidence of mandible RIC was higher in patients who received 3D-CRT (0.07%) than in those who received IMRT (0%). The proportion of mandible RICs was higher in patients who received 3D-CRT (16.667%) than in those who received IMRT (0%) and conventional 2D radiotherapy (3.529%). Regarding the histological type, the incidence of squamous cell carcinoma (SCC) was higher in patients who received conventional 2D radiotherapy (0.266%) than in those who received 3D-CRT (0.175%); patients who received IMRT had a higher proportion of SCC than those who received 3D-CRT/conventional 2D radiotherapy (86.4% vs. 41.7% vs. 74.2%); the incidence of sarcoma was higher in patients who received 3D-CRT (0.175%) than in those who received IMRT (0.025%); and the proportion of sarcoma was higher in patients who received 3D-CRT (41.667%) than in those who received IMRT (6.818%) and conventional 2D radiotherapy (17.647%). Patients who received surgery for RICs had better survival than those who received no surgery (64.49 vs. 12.42 months). In the univariate and multivariate analyses, surgery was an independent prognostic factor for overall survival.

CONCLUSIONS

Our results have implications for long-term follow-up of RIC, multidisciplinary management, and patient counseling of RIC after nasopharyngeal carcinoma treatment by treating clinicians.

Targeting anti-inflammatory immunonanocarriers to human and murine neutrophils via the Ly6 antigen for psoriasiform dermatitis alleviation

Psoriasis is a refractory and difficult-to-treat skin disorder. The neutrophil-targeting approach represents a promising option for psoriasis therapy. This study developed and examined NIMP-R14-conjugated immunonanoparticles for specific targeting to neutrophils associated with psoriasiform dermatitis. In the process, roflumilast (RFL), as a phosphodiesterase (PDE) 4 inhibitor, was encapsulated in the nanocarriers to assess the anti-inflammatory capability against primary neutrophil activation and murine psoriasiform lesion. The average size and surface charge of the immunonanocarriers were 305 ± 36 nm and -18 ± 6 mV, respectively. The monovalent antibody-conjugated nanoparticles offered precise uptake by both human and mouse neutrophils but failed to exhibit this effect in monocytes and lymphocytes. The intracellular RFL concentration of the immunonanocarriers was five-fold superior to that of the passive counterparts. The immunonanocarriers specifically recognized the neutrophils through the Ly6 antigen with no apparent cytotoxicity. The antibody-conjugated nanoparticles mitigated superoxide anion production and migration of the activated human neutrophils. The in vivo biodistribution in the psoriasiform mice, found using an in vivo imaging system (IVIS) and liquid chromatography (LC)-mass-mass analysis, showed that the antibody conjugation increased the nanoparticle residence in systemic circulation after intravenous administration. On the other hand, most of the nanoparticles were accumulated in the lesional skin after subcutaneous injection. The actively-targeted nanocarriers were better than the free RFL and unfunctionalized nanoparticles in suppressing psoriasiform inflammation. The immunonanocarriers reduced neutrophil recruitment and epidermal hyperplasia in the plaque. Intravenous and subcutaneous treatments with the immunonanocarriers significantly reduced the overexpressed cytokines and chemokines in the inflamed skin, demonstrating that the nanosystems could both systematically and locally alleviate inflammation. The results indicated that the NIMP-R14-conjugated RFL-loaded nanoparticles have potential as an anti-autoimmune disease delivery system for neutrophil targeting.

Polydopamine/IR820 nanoparticles as topical phototheranostics for inhibiting psoriasiform lesions through dual photothermal and photodynamic treatments

Dual photothermal and photodynamic therapy (PTT and PDT) is an attractive approach that generates a synergistic effect for inhibiting keratinocyte hyperproliferation in the treatment of psoriasis. Here, we developed phototheranostic nanocarriers capable of producing hyperthermia and reactive oxygen species (ROS) in response to near-infrared (NIR) illumination. To this end, IR820 with photothermal and photodynamic features was embedded in nano-sized polydopamine (PDA) acting as a PTT agent. A comprehensive characterization of the PDA/IR820 nanosystem was performed according to its morphology, size, zeta potential, UV absorbance, and heat generation. Its therapeutic efficacy was assessed by a keratinocyte-based study and using an imiquimod (IMQ)-stimulated psoriasiform murine model. PDA/IR820 nanoparticles were facilely internalized into keratinocytes and mainly resided in lysosomes. Upon irradiation with NIR light, ROS were generated inside the keratinocytes to cause a photodynamic effect. The live/dead cell assay and cytotoxicity assay demonstrated that PDA and IR820 acted as effective photoabsorbers to induce keratinocyte death. The highest cytotoxic effect was detected in the group of NIR-irradiated PDA/IR820 nanoparticles, which killed 52% of keratinocytes. The nanosystem acted through the caspase and poly ADP-ribose polymerase (PARP) pathways to induce keratinocyte apoptosis. In vitro and in vivo skin permeation indicated the selective accumulation of the topically applied PDA/IR820 nanoparticles within psoriasiform skin, suggesting their skin-targeting capability. The combination of PDA/IR820 nanoparticles and NIR irradiation increased the skin temperature by 11.7 °C. PTT/PDT eliminated psoriasiform plaques in mice by decreasing hyperplasia, inhibiting cytokine overexpression, and recovering the barrier function. The epidermal thickness of the IMQ-treated skin was reduced from 134 to 34 μm by the nanocarriers plus NIR. The IR820 nanoparticles were largely deposited on the inflamed areas of psoriasiform lesions for monitoring the severity of inflammation. The image-guided phototheranostic nanoparticles showed their potential for applications in psoriasis management via noninvasive topical administration.

The Potential Implications of Hydrogen Sulfide in Aging and Age-Related Diseases through the Lens of Mitohormesis

The growing increases in the global life expectancy and the incidence of chronic diseases as a direct consequence have highlighted a demand to develop effective strategies for promoting the health of the aging population. Understanding conserved mechanisms of aging across species is believed helpful for the development of approaches to delay the progression of aging and the onset of age-related diseases. Mitochondrial hormesis (or mitohormesis), which can be defined as an evolutionary-based adaptive response to low-level stress, is emerging as a promising paradigm in the field of anti-aging. Depending on the severity of the perceived stress, there are varying levels of hormetic response existing in the mitochondria called mitochondrial stress response. Hydrogen sulfide (H₂S) is a volatile, flammable, and toxic gas, with a characteristic odor of rotten eggs. However, H₂S is now recognized an important gaseous signaling molecule to both physiology and pathophysiology in biological systems. Recent studies that elucidate the importance of H₂S as a therapeutic molecule has suggested its protective effects beyond the traditional understanding of its antioxidant properties. H₂S can also be crucial for the activation of mitochondrial stress response, postulating a potential mechanism for combating aging and age-related diseases. Therefore, this review focuses on highlighting the involvement of H₂S and its sulfur-containing derivatives in the induction of mitochondrial stress response, suggesting a novel possibility of mitohormesis through which this gaseous signaling molecule may promote the healthspan and lifespan of an organism.

Laser-assisted nanocarrier delivery to achieve cutaneous siRNA targeting for attenuating psoriasiform dermatitis

Psoriasis is an autoimmune skin disorder presenting the excessive expression of interleukin (IL)-6. The topical use of small interfering RNA (siRNA) has been increasingly discovered for treating skin diseases. A delivery system capable of protecting siRNA while facilitating both skin targeting and cellular entrance is critical for the successful medication of topically-applied siRNA. Herein, we developed a delivery system for siRNA based on poly(lactic-co-glycolic acid) (PLGA) nanoparticles and combined this system with an ablative laser to promote skin absorption for topical psoriasis therapy. The siRNA absorption enhancement was compared by two laser modalities: a fractional CO₂ laser and a fully-ablative Er:YAG laser. We characterized the effect of the delivery system by the cellular uptake, IL-6 silencing, in vitro skin absorption, cutaneous biodistribution, and in vivo psoriasiform dermatitis in mice. The nanocarriers showed minimal cytotoxicity and facile cellular uptake to knock down the IL-6 expression. The nanoformulation containing a cationic surfactant (Forestall) for ion pairing with siRNA achieved a 66% and 77% IL-6 knockdown efficiency toward keratinocytes and macrophages, respectively. In the Franz cell absorption, the lasers increased the naked siRNA penetration to the receptor compartment by 3.7-5.0-fold but remarkably reduced skin deposition using imiquimod (IMQ)-treated psoriasiform skin as the barrier. The fractional laser facilitated nanoparticle-associated siRNA skin deposition up to 3.3-fold, whereas the transport of the nanocarriers to the receptor was negligible. Qualitatively, the lasers increased nanoparticle delivery in the epidermis with limited effect to elevate the penetration depth. The fractional-mediated nanocarrier delivery dramatically attenuated the erythema and scaly lesions of psoriasiform dermatitis. The histological examination displayed a reduction of epidermal hyperplasia and macrophage infiltration by the combination of laser and nanosystem. The passive and laser-assisted naked siRNA delivery was less effective in mitigating dermatitis. The topical delivery of fractional laser-assisted nanoparticles on mice resulted in a 56% IL-6 knockdown. Our results manifested the benefit of cutaneous siRNA targeting using ablative lasers to deliver nanocarriers for treating psoriatic inflammation.

Photothermal treatment by PLGA-gold nanorod-isatin nanocomplexes under near-infrared irradiation for alleviating psoriasiform hyperproliferation

Psoriasis is a chronic autoimmune skin disorder that involves keratinocyte hyperproliferation and inflammatory cell recruitment. A strategy to mitigate psoriatic lesions is to induce keratinocyte apoptosis for proliferation suppression. Herein we designed a nanoformulation capable of treating psoriasis via hyperthermia-induced apoptosis in response to near-infrared (NIR) irradiation. To this end, gold nanorods (GNRs) and isatin, which is an anti-inflammatory agent for synergizing antipsoriatic activity, were loaded into a poly (lactic-co-glycolic acid) (PLGA) matrix to form the nanocomplexes. The physicochemical and photothermal properties of the nanocomplexes were determined in terms of size, surface charge, NIR-absorbing feature, isatin release, keratinocyte uptake, and cytotoxicity. The nanocomplexes showed a spherical shape with an average size of about 180 nm. The GNR-loaded nanoparticles can efficiently convert NIR light at 0.42 W/cm² into heat with an increased temperature of 10 °C. When combined with NIR exposure, the nanocomplexes were internalized into keratinocyte cytoplasm with an inhibition of keratinocyte viability to about 60%. Live/dead cell assay and flow cytometry confirmed that the nanocomplexes could serve as NIR-absorbers to specifically elicit keratinocyte apoptosis through caspase and poly ADP-ribose polymerase (PARP) pathways. The in vivo psoriasiform murine model indicated that the combined nanocomplexes and NIR inhibited epidermal hyperplasia and neutrophil infiltration. The overexpressed cytokines in the lesion could be recovered to normal baseline level after the photothermal management. The subcutaneous nanocomplexes remained in the skin for at least 5 days. The nanocomposites produced a negligible toxicity in the skin or liver of healthy mice. The photothermal nanosystems, as designed in this study, shed new light on the therapeutic approach against psoriasis.

Monovalent antibody-conjugated lipid-polymer nanohybrids for active targeting to desmoglein 3 of keratinocytes to attenuate psoriasiform inflammation

To improve the treatment of psoriasiform inflammation, we developed actively targeted nanocarriers loaded with the phosphodiesterase 4 inhibitor AN2728. Methods: Phospholipid-poly(lactic-co-glycolic acid) nanohybrids were prepared and conjugated with monovalent anti-desmoglein 3 antibody to bind keratinocytes. Results: The actively targeted nanohybrids were 229 nm in mean size with a nearly neutral surface charge. Flow cytometry and confocal microscopy showed a 9-fold increase in keratinocyte uptake of targeted nanohybrids relative to non-targeted nanoparticles. The nanoparticles localized mainly in lysosomes after internalization. AN2728-loaded antibody-conjugated nanocarriers inhibited cytokine/chemokine overexpression in activated keratinocytes without affecting cell viability. The targeted nanohybrids also suppressed neutrophil migration by reducing CXCL1 and CXCL2 release from keratinocytes. Following subcutaneous administration in mice, the nanohybrids distributed to the epidermis and hair follicles. In a psoriasis-like skin mouse model, the actively targeted nanoparticles were superior to free drug and non-targeted nanoparticles in mitigating skin inflammation. Intervention with the targeted nanosystem reduced the epidermal thickness of the psoriasiform lesion from 191 to 42 µm, decreased the Psoriasis Area Severity Index by 74%, restored barrier function, and returned chemokine levels to baseline. Conclusions: Our developed nanosystem was safe and demonstrated efficient targeting properties for the treatment of cutaneous inflammation.

Facile skin targeting of a thalidomide analog containing benzyl chloride moiety alleviates experimental psoriasis via the suppression of MAPK/NF-κB/AP-1 phosphorylation in keratinocytes

BACKGROUND

Thalidomide can be a TNF-α inhibitor for treating skin inflammation. This drug exhibits a strong toxicity that limits its application.

OBJECTIVE

We synthesized a thalidomide analog containing the benzyl chloride group (2-[1-(3-chlorobenzyl)-2,6-dioxopiperidin-3-yl]isoindoline-1,3-dione, CDI) to examine anti-inflammatory activity against psoriasis.

METHODS

The evaluation was conducted by the experimental platforms of in vitro TNF-α- or imiquimod (IMQ)-stimulated HaCaT cells and in vivo IMQ-induced psoriasiform plaque.

RESULTS

Using the in vitro keratinocyte model, we demonstrated a greater inhibition of IL-1β, IL-6, and IL-24 by CDI than by thalidomide. No significant cytotoxicity was observed at 100 μM. CDI delivered facilely into the skin with a cutaneous targeting ability 228-fold greater than thalidomide. CDI caused a negligible irritation on healthy mouse skin. We showed that topically applied CDI reduced IMQ-induced red scaly lesions, hyperplasia, microabscesses, and cytokine expression in the mouse model. The skin-barrier function measured by transepidermal water loss (TEWL) could be partially recovered from 50.6-36.3 g/m²/h by CDI. The mechanistic study showed that CDI suppressed cytokine production by inhibiting the phosphorylation of NF-κB and AP-1 via MAPK pathways.

CONCLUSION

CDI would be beneficial for the development of a therapeutic agent against psoriasis.

Haemodynamics as a determinant of need for pre-hospital application of a pelvic circumferential compression device in adult trauma patients

INTRODUCTION

Pelvic ring fractures are common following high-energy blunt trauma and can lead to substantial haemorrhage, morbidity and mortality. Pelvic circumferential compression devices (PCCDs) improve position and stability of open-book type pelvic fracture, and can improve haemodynamics in patients with hypovolaemic shock. However, PCCDs may cause adverse outcomes including worsening of lateral compression fracture patterns and routine use is associated with high costs. Controversy regarding indication of PCCDs exists with some centres recommending PCCD in the setting of hypovolaemic shock compared to placement for any suspected pelvic injury.

OBJECTIVE

To assess the need for PCCD application based on pre-hospital vital signs and mechanism of injury.

METHODS

A retrospective cohort study was conducted in a single adult major trauma centre examining a 2-year period. Patients were sub-grouped based on initial pre-hospital and emergency department observations as haemodynamically normal (heart rate <100 bpm, systolic blood pressure ≥100 mmHg and Glasgow Coma Scale ≥13) or abnormal. Diagnostic accuracy of pre-hospital haemodynamics as a predictor of pelvic fracture requiring intervention within 24 h was assessed.

RESULTS

There were 376 patients with PCCD in-situ on hospital arrival. Pelvic fractures were diagnosed in 137 patients (36.4%). Of these, 39 (28.5%) were haemodynamically normal and 98 (71.5%) were haemodynamically abnormal. The most common mechanisms of injury were motor vehicle collision (57.7%) and motorcycle collision (13.8%). Of those with fractures, 40 patients (29.2%) required pelvic intervention within 24 h of admission; of these, 8 (20%) were haemodynamically normal and 32 (80%) were haemodynamically abnormal. As a test for pelvic fracture requiring intervention within 24 h, abnormal pre-hospital haemodynamics had a sensitivity of 0.80 (95% CI 0.64-0.91), specificity of 0.32 (95% CI 0.27-0.38) and negative predictive value (NPV) of 0.93 (95% CI 0.88-0.96). Combined with absence of a major mechanism of injury, normal haemodynamics had a sensitivity 1.00, specificity 0.51 (95% CI 0.36-0.66) and NPV of 1.00 for pelvic intervention within 24 h.

CONCLUSION

Normal haemodynamic status, combined with absence of major mechanism of injury can rule out requirement for urgent pelvic intervention. Ongoing surveillance is recommended to monitor for any adverse effects of this change in practice.

Cutaneous delivery of [1-(4-chloro-3-nitrobenzenesulfonyl)-1H-indol-3-yl]-methanol, an indole-3-carbinol derivative, mitigates psoriasiform lesion by blocking MAPK/NF-κB/AP-1 activation

[1-(4-chloro-3-nitrobenzenesulfonyl)-1H-indol-3-yl]-methanol (CIM) has been used as a bioactive agent for inhibiting tumor growth and angiogenesis via mitogen-activated protein kinase (MAPK) and NF-κB blocking. The present work was undertaken to investigate the potential of CIM against psoriasis using imiquimod (IMQ)-stimulated psoriasis-like mouse and in vitro HaCaT keratinocytes as the models. We demonstrated that topical CIM treatment reduced IMQ-activated scaling, erythema, and barrier dysfunction. This compound also restrained the recruitment of neutrophils. The cytokines, including TNF-α, IL-1β, IL-6, and IL-17 in psoriasiform skin, can be attenuated to normal baseline by CIM. Topically applied CIM can be easily delivered into skin based on the affinity with stratum corneum (SC) ceramides. IMQ intervention increased the permeability by 3-fold as compared to healthy skin. CIM ameliorated psoriatic lesion without incurring overt signs of irritation. Both TNF-α and IMQ were employed as the stimulators to activate HaCaT for reciprocal elucidation of the mechanism of action. CIM inhibited the overexpression of IL-1β, IL-6, and IL-24 in HaCaT. CIM exerted anti-inflammatory activity by suppressing the phosphorylation of NF-κB and activator protein-1 (AP-1) through MAPK pathways. Our results indicate that CIM has potential as the antipsoriatic molecule. The detailed signaling pathways still need further investigation.

Topical application of anthranilate derivatives ameliorates psoriatic inflammation in a mouse model by inhibiting keratinocyte-derived chemokine expression and neutrophil infiltration

Psoriasis is an inflammatory autoimmune skin disorder possessing a complex etiology related to genetic and environmental triggers. Keratinocytes show a potential role for the origin of psoriasis. In this study, we estimated the efficiency of 2 anthranilate derivatives-(E)-4-( N-{2-[1-(hydroxyimino)ethyl]phenyl}sulfamoyl)phenyl pivalate (HFP031) and butyl 2-[2-(2-fluorophenyl)acetamido]benzoate (HFP034)-on psoriasis amelioration in a mouse model. The results showed that topical treatment with both compounds could attenuate epidermal thickness and scaling in an imiquimod (IMQ)-induced psoriasis mouse model via decreased expression of cytokines and chemokines [C-X-C chemokine ligand (CXCL)1 and CXCL2], leading to the reduction of neutrophilic abscess in the skin. The in vivo cutaneous absorption of HFP034 was 7.6-fold greater than that of HFP031. Both compounds caused negligible irritation on healthy mouse skin. In addition, we examined the effect of the anthranilate derivatives on chemokine expression in IMQ-treated HaCaT keratinocytes. Our results elucidated a mechanism for anti-inflammatory activity of HFP034 that involved the elevation of intracellular cAMP concentration, suppression of NF-κB activity, and attenuation of neutrophil chemoattractant expression. These results suggest that HFP034 could increase the cutaneous concentration of cAMP to suppress neutrophil infiltration into the skin. Topically applied HFP034 may demonstrate a potential for future clinical application as a novel therapy for psoriasis treatment.-Lin, Z.-C., Hsieh, P.-W., Hwang, T.-L., Chen, C.-Y., Sung, C. T., Fang, J.-Y. Topical application of anthranilate derivatives ameliorates psoriatic inflammation in a mouse model by inhibiting keratinocyte-derived chemokine expression and neutrophil infiltration.

Artocarpin, an isoprenyl flavonoid, induces p53-dependent or independent apoptosis via ROS-mediated MAPKs and Akt activation in non-small cell lung cancer cells

Artocarpin has been shown to exhibit cytotoxic effects on different cancer cells, including non-small cell lung carcinoma (NSCLC, A549). However, the underlying mechanisms remain unclear. Here, we explore both p53-dependent and independent apoptosis pathways in artocarpin-treated NSCLC cells. Our results showed that artocarpin rapidly induced activation of cellular protein kinases including Erk1/2, p38 and AktS473. Inhibition of these protein kinases prevented artocarpin-induced cell death. Moreover, artocarpin-induced phosphorylation of these protein kinases and apoptosis were mediated by induction of reactive oxygen species (ROS), as pretreatment with NAC (a ROS scavenger) and Apocynin (a Nox-2 inhibitor) blocked these events. Similarly, transient transfection of p47Phox or p91Phox siRNA attenuated artocarpin-induced NADPH oxidase activity and cell death. In addition, p53 dependent apoptotic proteins including PUMA, cytochrome c, Apaf-1 and caspase 3 were activated by artocarpin, and these effects can be abolished by antioxidants, MAPK inhibitors (U0126 and SB202190), but not by PI3K inhibitor (LY294002). Furthermore, we found that artocarpin-induced Akt phosphorylation led to increased NF-κB activity, which may act as an upstream regulator in the c-Myc and Noxa pathway. Therefore, we propose that enhancement of both ERK/ p38/ p53-dependent or independent AktS473/NF-κB/c-Myc/Noxa cascade by Nox-derived ROS generation plays an important role in artocarpin-induced apoptosis in NSCLC cells.

Magnolol Nanoparticles Exhibit Improved Water Solubility and Suppress TNF-α-Induced VCAM-1 Expression in Endothelial Cells

The expression of the adhesion molecule vascular cell adhesion molecule-1 (VCAM-1) on endothelial cells enables the attachment of leukocytes to the endothelium, which may lead to inflammation and the development of atherosclerosis. Magnolol is a major bioactive compound derived from the plant species Magnolia officinalis. In this study, we synthesized a novel nanoparticle formulation of magnolol to improve its water solubility and physicochemical properties, evaluated its effects on TNF-α-induced VCAM-1 expression in endothelial cells, and determined the signal transduction pathways involved. Our findings demonstrated that the magnolol nanoparticle system showed great improvements in physicochemical properties and water solubility owing to a reduction in particle size, transformation from a crystalline to amorphous structure, and the formation of hydrogen bonds with the nanoparticle carriers. In terms of its biological actions, magnolol nanoparticles attenuated TNF-α-induced VCAM-1 protein expression, promoter activity, and mRNA expression in endothelial cells in vitro. This was found to be mediated by the ERK, AKT, and NF-κB signaling pathways. In addition, magnolol nanoparticles inhibited TNF-α-induced leukocyte adhesion to endothelial cells, and suppressed TNF-α-induced VCAM-1 expression in the aortic endothelium of mice. In summary, since magnolol nanoparticles inhibit endothelial VCAM-1 expression and leukocyte adhesion to endothelial cells, this novel drug formulation may be a potentially useful therapeutic formulation to prevent the development of atherosclerosis and inflammatory diseases.

Immunotolerant indoleamine-2,3-dioxygenase is increased in condyloma acuminata

BACKGROUND

The tryptophan-depleting enzyme indoleamine-2,3-dioxygenase (IDO) is critical for the regulation of immunotolerance and plays an important role in immune-associated skin diseases.

OBJECTIVES

To analyse the level of IDO in condyloma acuminata (CA) and its role in this condition.

METHODS

IDO expression was assessed in the skin and peripheral blood of healthy controls and patients with CA. To assess the role of skin IDO in immunity, the ability of isolated epidermal cells to metabolize tryptophan and the influence on polyclonal T-cell mitogen (PHA)-stimulated T-cell proliferation were explored.

RESULTS

IDO median fluorescence intensities in peripheral blood mononuclear cells from patients with CA were similar to those from healthy controls. Immunohistochemistry showed that IDO⁺ cells were rare in normal skin and the control skin of patients with CA, but were greatly accumulated in wart tissue. Most fluorescence signals of IDO⁺ cells did not overlap with those of CD1a⁺ Langerhans cells. Human papillomavirus (HPV) DNA probe in situ hybridization showed a large number of IDO⁺ cells in the HPV^- site. Keratinocytes in the skin of healthy controls and the circumcised skin of patients with CA could minimally transform tryptophan into kynurenine, but IDO-competent epidermal cells from warts could transform tryptophan. In addition, these IDO-competent epidermal cells could inhibit PHA-stimulated T-cell proliferation. The addition of an IDO inhibitor, 1-methyl-d-tryptophan, restored the inhibited T-cell proliferation.

CONCLUSIONS

Abnormally localized high IDO expression might be involved in the formation of a local immunotolerant microenvironment.

Recent advances in oral delivery of drugs and bioactive natural products using solid lipid nanoparticles as the carriers

Chemical and enzymatic barriers in the gastrointestinal (GI) tract hamper the oral delivery of many labile drugs. The GI epithelium also contributes to poor permeability for numerous drugs. Drugs with poor aqueous solubility have difficulty dissolving in the GI tract, resulting in low bioavailability. Nanomedicine provides an opportunity to improve the delivery efficiency of orally administered drugs. Solid lipid nanoparticles (SLNs) are categorized as a new generation of lipid nanoparticles consisting of a complete solid lipid matrix. SLNs used for oral administration offer several benefits over conventional formulations, including increased solubility, enhanced stability, improved epithelium permeability and bioavailability, prolonged half-life, tissue targeting, and minimal side effects. The nontoxic excipients and sophisticated material engineering of SLNs tailor the controllable physicochemical properties of the nanoparticles for GI penetration via mucosal or lymphatic transport. In this review, we highlight the recent progress in the development of SLNs for disease treatment. Recent application of oral SLNs includes therapies for cancers, central nervous system-related disorders, cardiovascular-related diseases, infection, diabetes, and osteoporosis. In addition to drugs that may be active cargos in SLNs, some natural compounds with pharmacological activity are also suitable for SLN encapsulation to enhance oral bioavailability. In this article, we systematically introduce the concepts and amelioration mechanisms of the nanomedical techniques for drug- and natural compound-loaded SLNs.

Eupafolin nanoparticles protect HaCaT keratinocytes from particulate matter-induced inflammation and oxidative stress

Exposure to particulate matter (PM), a major form of air pollution, can induce oxidative stress and inflammation and may lead to many diseases in various organ systems including the skin. Eupafolin, a flavonoid compound derived from Phyla nodiflora, has been previously shown to exhibit various pharmacological activities, including antioxidant and anti-inflammatory effects. Unfortunately, eupafolin is characterized by poor water solubility and skin penetration, which limits its clinical applications. To address these issues, we successfully synthesized a eupafolin nanoparticle delivery system (ENDS). Our findings showed that ENDS could overcome the physicochemical drawbacks of raw eupafolin with respect to water solubility and skin penetration, through reduction of particle size and formation of an amorphous state with hydrogen bonding. Moreover, ENDS was superior to raw eupafolin in attenuating PM-induced oxidative stress and inflammation in HaCaT keratinocytes, by mediating the antioxidant pathway (decreased reactive oxygen species production and nicotinamide adenine dinucleotide phosphate oxidase activity) and anti-inflammation pathway (decreased cyclooxygenase-2 expression and prostaglandin E2 production through downregulation of mitogen-activated protein kinase and nuclear factor-κB signaling). In summary, ENDS shows better antioxidant and anti-inflammatory activities than raw eupafolin through improvement of water solubility and skin penetration. Therefore, ENDS may potentially be used as a medicinal drug and/or cosmeceutical product to prevent PM-induced skin inflammation.

Eupafolin ameliorates COX-2 expression and PGE2 production in particulate pollutants-exposed human keratinocytes through ROS/MAPKs pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Eupafolin is a major bioactive compound derived from the methanolic extract of the medicinal herb Phyla nodiflora, which has been used in traditional Chinese medicine to treat various inflammatory diseases. Recently, particulate air pollutants have been shown to induce inflammation of the skin. In this study, we seek to determine whether eupafolin can inhibit the production of inflammatory mediators in a human skin keratinocyte cell line exposed to particulate air pollutants (particulate matter, PM), and determine the molecular mechanisms involved.

MATERIALS AND METHODS

Human keratinocyte HaCaT cells were treated with PM in the presence or absence of eupafolin. Cyclooxygenase-2 (COX-2) protein and gene expression levels were determined by Western blotting, RT-PCR and luciferase activity assay. Prostaglandin E2 (PGE2) production was evaluated by the enzyme immunoassay method. Generation of intracellular reactive oxygen species (ROS) was measured by the dichlorofluorescin (DCFH) oxidation assay, and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity was determined by a chemiluminescence assay. For in vivo studies, COX-2 expression in the skin of BALB/c nude mice was analyzed by immunohistochemistry.

RESULTS

Eupafolin inhibited PM-induced COX-2 protein and gene expression and PGE2 production in HaCaT cells. In addition, eupafolin suppressed PM-induced intracellular ROS generation, NADPH oxidase activity, MAPK (ERK, JNK and p38) activation and NK-κB activation. In vivo studies showed that topical treatment with eupafolin inhibited COX-2 expression in the epidermal keratinocytes of PM-treated mice.

CONCLUSIONS

Eupafolin exerts anti-inflammatory and antioxidant effects on skin keratinocytes exposed to particulate air pollutants, and may have potential use in the treatment or prevention of air pollutant-induced inflammatory skin diseases in the future.

Urban particulate matter down-regulates filaggrin via COX2 expression/PGE2 production leading to skin barrier dysfunction

We explored the regulation of filaggrin, cyclooxygenase 2 (COX2) and prostaglandin E2 (PGE2) expression induced by urban particulate matter (PM) in human keratinocytes. In addition, we investigated the signaling pathways involved in PM-induced effects on COX2/PGE2 and filaggrin. PMs induced increases in COX2 expression and PGE2 production, and decreased filaggrin expression. These effects were attenuated by pretreatment with COX2 inhibitor and PGE2 receptor antagonist, or after transfection with siRNAs of the aryl hydrocarbon receptor (AhR), gp91phox and p47phox. Furthermore, PM-induced generation of reactive oxygen species (ROS) and NADPH oxidase activity was attenuated by pretreatment with an AhR antagonist (AhRI) or antioxidants. Moreover, Nox-dependent ROS generation led to phosphorylation of ERK1/2, p38, and JNK, which then activated the downstream molecules NF-κB and AP-1, respectively. In vivo studies in PMs-treated mice showed that AhRI and apocynin (a Nox2 inhibitor) had anti-inflammatory effects by decreasing COX2 and increasing filaggrin expression. Our results reveal for the first time that PMs-induced ROS generation is mediated through the AhR/p47 phox/NADPH oxidase pathway, which in turn activates ERK1/2, p38/NF-κB and JNK/AP-1, and which ultimately induces COX2 expression and filaggrin downregulation. Up-regulated expression of COX2 and production of PGE2 may lead to impairment of skin barrier function.

Serum uric acid predicts cardiovascular mortality in male peritoneal dialysis patients with diabetes

BACKGROUND AND AIMS

Serum uric acid may predict mortality in diabetic patients and dialysis patients. However, the relationship between serum uric acid and prognosis in diabetic peritoneal dialysis (PD) patients is unclear.

METHODS AND RESULTS

We conducted a cohort study of 1278 incident PD patients, (mean age 47.6 years), of which 328 (25.7%) had diabetes and 289 (22.6%) had diabetic nephropathy. During a median follow-up period of 30.7 months, 231 deaths occurred, of which 126 were ascribed to cardiovascular events. Mean serum uric acid was lower for diabetic patients than non-diabetic patients (6.8 ± 1.3 vs. 7.4 ± 1.4 mg/dL, respectively; P < 0.001). Cox regression models were adjusted for glycated hemoglobin, dialysis-related factors, traditional risk factors, and treatments. After adjustments, the highest sex-specific tertile of uric acid was associated with an increased risk of cardiovascular mortality (HR, 2.26; 95% CI, 1.14-4.48) compared to the lowest tertile in diabetic patients. Adjusted HRs per 1 mg/dL higher uric acid for all-cause and cardiovascular mortality were 1.09 (95% CI, 0.91-1.32) and 1.42 (95% CI, 1.13-1.79) for diabetic men and 1.06 (95% CI, 0.83-1.35) and 1.12 (95% CI, 0.78-1.61) for diabetic women, respectively. Elevated serum uric acid predicted a higher risk of all-cause and cardiovascular mortality in non-diabetic men but not in non-diabetic women.

CONCLUSIONS

Elevated serum uric acid is an independent predictor of cardiovascular mortality in diabetic male PD patients.

Eupafolin inhibits PGE2 production and COX2 expression in LPS-stimulated human dermal fibroblasts by blocking JNK/AP-1 and Nox2/p47(phox) pathway

Eupafolin, a major active component found in the methanol extracts of Phyla nodiflora, has been used to treat inflammation of skin. We examined its effects on cyclooxygenase-2 (COX-2) expression in LPS-treated human dermal fibroblasts. Lipopolysaccharide (LPS) significantly increased prostaglandin-E2 (PGE2) production associated with increased COX-2 expression in Hs68 cells. This effect was blocked by eupafolin, TLR-4 antibody, antioxidants (APO and NAC), as well as inhibitors, including U0126 (ERK1/2), SB202190 (p38), SP600125 (JNK1/2), and Tanshinone IIA (AP-1). In gene regulation level, qPCR and promoter assays revealed that COX-2 expression was attenuated by eupafolin. In addition, eupafolin also ameliorated LPS-induced p47 phox activation and decreased reactive oxygen species (ROS) generation and NADPH oxidase (Nox) activity. Moreover, pretreatment with eupafolin and APO led to reduced LPS-induced phosphorylation of ERK1/2, JNK, and p38. Further, eupafolin attenuated LPS-induced increase in AP-1 transcription factor binding activity as well as the increase in the phosphorylation of c-Jun and c-Fos. In vivo studies have shown that in dermal fibroblasts of LPS treated mice, eupafolin exerted anti-inflammation effects by decreasing COX-2 protein levels. Our results reveal a novel mechanism for anti-inflammatory and anti-oxidative effects of eupafolin that involved inhibition of LPS-induced ROS generation, suppression of MAPK phosphorylation, diminished DNA binding activity of AP-1 and attenuated COX-2 expression leading to reduced production of prostaglandin E2 (PGE2). Our results demonstrate that eupafolin may be used to treat inflammatory responses associated with dermatologic diseases.

Psychiatric disturbances regulate the innate immune system in CSF of conscious mice

Environment may affect brain activity through cerebrospinal fluid (CSF) only if there are regulatory molecules or cascades in CSF that are sensitive to external stimuli. This study was designed to identify regulatory activity present in CSF, better elucidating environmental regulation of brain function. By using cannulation-based sequential CSF sampling coupled with mass spectrometry-based identification and quantification of proteins, we show that the naive mouse CSF harbors, among 22 other pathways, the innate immune system as a main pathway, which was downregulated and upregulated, respectively, by acute stressor (AS) and acute cocaine (AC) administrations. Among novel processes and molecular functions, AS also regulated schizophrenia-associated proteins. Furthermore, AC upregulated exosome-related proteins with a false discovery rate of 1.0 × 10(-)(16). These results suggest that psychiatric disturbances regulate the neuroimmune system and brain disorder-related proteins, presenting a sensitive approach to investigating extracellular mechanisms in conscious and various mouse models of psychiatric disorders.

Mobility asymmetry in InGaAs/InAlAs heterostructures with InAs quantum wires

Strong asymmetry of electron mobility in InGaAs/InAlAs heterostructures (lattice matched to InP) with the presence of InAs quantum wires was observed. Self-assembled InAs quantum wires, embedded in an InGaAs matrix close to the hetero-interface, has a strong effect in electron conduction in the interface channel. The low temperature mobility for electrons moving parallel to the quantum wires is much higher than that of electrons moving perpendicular to the wires. The asymmetry in mobility is attributed to the difference in scattering cross section of the quantum wires in these two directions.

The possibility of GST antigen from Chinese strain of Schistosoma japonicum for immunodiagnosis of schistosomiasis

The GST antigen (called 26-28 kDa antigen) extracted and purified from Schistosoma japonicum adult worms was applied to the detection of specific antibodies in sera of infected mice and mice immunized with the above protein antigen by ELISA technique. The 26-28 kDa antigen was better than crude antigens (SEA, SWAP) when used to detect specific antibodies in sera from immunized mice. As with crude antigens (SEA and SWAP), the 26-28 kDa antigen could be used to detect specific antibodies in infected sera, with titers as high as 1:160-1:320. There were no false positive reactions and a positivity rate as high as that using SWAP occurred when the 26-28 kDa antigen was used in schistosomiasis patients and normal subjects by intradermal test. It is suggested that the 26-28 kDa antigen may be a suitable candidate for immunodiagnosis of schistosomiasis.

[Incidence of venous air embolism in parturients during cesarean section with regional anesthesia]

The purpose of the study is to probe the situation of venous air embolism (VAE) and the accompanying complications occurring in Chinese parturients in Taiwan during Cesarean section. Sixty ASA physical status class I-II parturients who were subjected to cesarean section under regional anesthesia were evaluated. The sensor of the Doppler device was placed on the anterior chest to detect the rumbles of air when it came to pass, and simultaneously the signs and symptoms following VAE were observed. Our results demonstrated that the usual or normal Doppler heart sound changed in 38 parturients out of 60 (63.3%), and the alteration occurred very often when the uterus was being incised (81.6%), or sutured (97.4%), and concurred strong correlation with such signs and symptoms such as chest tightness or precordial pain (78.9%), shortness of breath (60.5%), and change of heart rate or blood pressure (86.8%). The method of anesthesia (spinal or epidural block) did not have effect on the occurrence of VAE, but different surgical approaches and different positions in which the patients were posed during operation did apparently bring about VAE of variable degree. Besides, supplying of oxygen could mitigate the symptoms produced by VAE. Consequently, the application of Doppler monitor during Cesarean section can detect VAE earlier and more efficiently and thus provides information timely treatment.