Tanshinol ameliorates imiquimod-induced psoriasis by inhibiting M1 macrophage polarization through suppression of the notch signaling pathway.

Psoriasis is a common immune-related chronic inflammatory skin disease, often accompanied by significant itching, and once diseased, the course of the disease lasts for most of the lifetime. Tanshinol (TAN) is an active ingredient of Salvia miltiorrhiza, which possesses pharmacological effects such as anti-inflammatory and antioxidant properties. However, the effects of TAN on psoriasis have not been widely reported. Therefore, the aim of this study was to investigate the therapeutic effects and mechanisms of TAN in psoriasis. An imiquimod (IMQ)-induced psoriasis mouse model was constructed and treated with different doses of TAN to observe the changes in skin lesion phenotype, macrophage polarization, inflammation and Notch signaling pathway in mice. Further removal of macrophages or inhibition or activation of Notch signaling pathway was performed to examine the changes in skin lesion phenotype, macrophage polarization, inflammation and Notch signaling pathway in mice. In addition, in vitro experiments verified that TAN regulates RAW264.7 macrophage polarization and cytokine secretion through the Notch pathway. The results showed that TAN alleviated IMQ-induced skin lesions and pathological phenotypes in psoriasis mice and inhibited Notch signaling pathway and M1-type macrophage polarization. Moreover, macrophage clearance and Notch signaling pathway activation inhibited the effect of TAN on psoriasis. Further in vitro experiments showed that Notch agonists reversed the effects of TAN on macrophage polarization and inflammatory cytokines. Collectively, these findings suggest that TAN may exert a therapeutic effect on psoriasis by inhibiting the Notch signaling pathway and thus M1-type macrophage polarization.

Liu J ，Yong S ，Yin S ，Feng J ，Lian C ，Chen J ... -  《-》

Cornuside alleviates psoriasis-like skin lesions in mice by relieving inflammatory effects.

Psoriasis is a chronic inflammatory skin disease substantially affecting the quality of life, with no complete cure owing to its complex pathogenesis. Cornuside, a major bioactive compound present in Cornus officinalis Sieb. et Zucc., which is a well-known traditional Chinese medicine with a variety of biological and pharmacological activities, such as anti-apoptotic, antioxidant, and anti-inflammatory properties. However, its effects on psoriasis remain unclear. Our preliminary analysis of network pharmacology showed that cornuside may be involved in psoriasis by regulating the inflammatory response and IL-17 signaling pathway. Thus, we investigated the protective role and mechanism of cornuside in the pathogenesis of psoriasis in an imiquimod (IMQ)-induced psoriasis mouse model. In-vivo experiments demonstrated that cornuside-treated mice had reduced skin erythema, scales, thickness, and inflammatory infiltration. The Psoriasis Area Severity Index score was significantly lower than that of the IMQ group. Flow cytometry analysis indicated that cornuside effectively inhibited Th1- and Th17-cell infiltration and promoted aggregation of Th2 cells in skin tissues. Cornuside also inhibited the infiltration of macrophages to the skin. Furthermore, in-vitro experiments indicated that cornuside also decreased the polarization of M1 macrophages and reduced the levels of associated cytokines. Western blotting demonstrated that cornuside suppressed the phosphorylation of c-Jun N-terminal kinase (JNK) and extracellular receptor kinase (ERK) in bone marrow-derived macrophages. Our findings indicate that cornuside has a protective effect against IMQ-induced psoriasis by inhibiting M1 macrophage polarization through the ERK and JNK signaling pathways and modulating the infiltration of immune cells as well as the expression of inflammatory factors.

Yan F ，Wang L ，Zhang J ，Liu Z ，Yu B ，Li W ，Guo Z ，Shi D ，Zhang H ，Xiong H ... -  《-》

4-1BBL Regulates the Polarization of Macrophages, and Inhibition of 4-1BBL Signaling Alleviates Imiquimod-Induced Psoriasis.

4-1BBL, a member of the TNF superfamily, regulates the sustained production of inflammatory cytokines in macrophages triggered by TLR signaling. In this study, we have investigated the role of 4-1BBL in macrophage metabolism and polarization and in skin inflammation using a model of imiquimod-induced psoriasis in mice. Genetic ablation or blocking of 4-1BBL signaling by Ab or 4-1BB-Fc alleviated the pathology of psoriasis by regulating the expression of inflammatory cytokines associated with macrophage activation and regulated the polarization of macrophages in vitro. We further linked this result with macrophage by finding that 4-1BBL expression during the immediate TLR response was dependent on glycolysis, mitochondrial oxidative phosphorylation, and fatty acid metabolism, whereas the late-phase 4-1BBL-mediated sustained inflammatory response was dependent on glycolysis and fatty acid synthesis. Correlating with this, administration of a fatty acid synthase inhibitor, cerulenin, also alleviated the pathology of psoriasis. We further found that 4-1BBL-mediated psoriasis development is independent of its receptor 4-1BB, as a deficiency of 4-1BB augmented the severity of psoriasis linked to a reduced regulatory T cell population and increased IL-17A expression in γδ T cells. Additionally, coblocking of 4-1BBL signaling and IL-17A activity additively ameliorated psoriasis. Taken together, 4-1BBL signaling regulates macrophage polarization and contributes to imiquimod-induced psoriasis by sustaining inflammation, providing a possible avenue for psoriasis treatment in patients.

Miki H ，Han KH ，Scott D ，Croft M ，Kang YJ ... -  《-》

PSORI-CM02 formula alleviates imiquimod-induced psoriasis via affecting macrophage infiltration and polarization.

Psoriasis is a refractory skin disease characterized by macrophage cell infiltrated in the dermal layer. Macrophages can simultaneously polarize into two distinct functional subtypes, M1 and M2, and this process is affected by the microenvironment, cytokines and JAK/STAT pathways. Formula PSORI-CM02 is a novel Chinese medicine used to alleviate psoriasis symptoms and regulate T cell differentiation and epithelial cell proliferation. However, the effects of PSORI-CM02 in imiquimod (IMQ)-induced psoriasis and macrophage infiltration and polarization in the dermis remain unknown. Imiquimod induced psoriasis mice model and M1/M2 polarization model on mice peritoneal macrophages cell line RAW264.7 in vitro were used to observe the therapeutic effect of PSORI-CM02 on skin and its molecular mechanisms. PSORI-CM02 can significantly improve skin lesions and reduce macrophage infiltration in mice induced by imiquimod. After treatment with PSORI-CM02 formula, M1 macrophage mediators were significantly reduced, while M2 mediators were significantly increased in mice. Similarly in vitro, M1 macrophage proliferation was suppressed and M2 macrophage proliferation was elevated by PSORI-CM02 in the presence of LPS and IL-4, respectively. The elevated expression of TNF-α, iNOS, and IL-1β induced by LPS was reduced, while the expression of Arg-1, Fizz-1, Ym-1, and IL-10 induced by IL-4 was elevated in PSORI-CM02-treated cells. Finally, we found that the effects of PSORI-CM02 in macrophage polarization were associated with regulation of STAT1 and STAT6 expression, which were activated by LPS and IL-4, respectively. Our novel findings reveal that PSORI-CM02 may possess therapeutic action in psoriasis treatment by regulating the infiltration and polarization of macrophages in the dermal layer.

Li L ，Zhang HY ，Zhong XQ ，Lu Y ，Wei J ，Li L ，Chen H ，Lu C ，Han L ... -  《-》

Orientin alleviates the inflammatory response in psoriasis like dermatitis in BALB/c mice by inhibiting the MAPK signaling pathway.

Psoriasis, a chronic inflammatory condition of the skin, is characterized by an atypical proliferation of epidermal keratinocytes and immune cell infiltration. Orientin is a flavonoid monomer with potent anti-inflammatory activities. However, the therapeutic effects of orientin on psoriasis and the underlying mechanisms have not been elucidated. To investigate the therapeutic effect of orientin on psoriasis and the underlying mechanisms using network pharmacology and experimental studies. A psoriasis-like mouse model was established using imiquimod (IMQ). Lipopolysaccharide (LPS) was used to stimulate the RAW264.7 and HaCaT cells in vitro. The therapeutic effects of orientin and the underlying mechanism were analyzed using histopathological, immunohistochemical, quantitative real-time polymerase chain reaction, enzyme-linked immunosorbent assay, flow cytometry, and western blotting analyses. Orientin ameliorated skin lesions and suppressed keratinocyte proliferation and immune cell infiltration in the IMQ-induced psoriasis-like mouse model. Additionally, orientin inhibited the secretion of the pro-inflammatory factors interleukin (IL)-1β, tumor necrosis factor (TNF)-α, IL-6, IL-8, IL-17, and IL-23 in the psoriasis-like mouse model and LPS-induced RAW264.7 and HaCaT cells. Furthermore, orientin mitigated the LPS-induced upregulation of reactive oxygen species and downregulation of IL-10 and glutathione levels. Orientin alleviated inflammation by downregulating the MAPK signaling pathway. Orientin alleviated psoriasis-like dermatitis by suppressing the MAPK signaling pathway, suggesting that orientin is a potential therapeutic for psoriasis.

Long Q ，Ma T ，Wang Y ，Chen S ，Tang S ，Wang T ，Zhou Y ，Xu K ，Wan P ，Cao Y ... -  《-》