Shikonin inhibits CEBPD downregulation in IL‑17‑treated HaCaT cells and in an imiquimod‑induced psoriasis model

Pharmacological Effects of Shikonin and Its Potential in Skin Repair: A Review

Currently, skin injuries have a serious impact on people's lives and socio-economic stress. Shikonin, a naphthoquinone compound derived from the root of the traditional Chinese medicine Shikonin, has favorable biological activities such as anti-inflammatory, antibacterial, immunomodulatory, anticancer, and wound-healing-promoting pharmacological activities. It has been reported that Shikonin can be used for repairing skin diseases due to its wide range of pharmacological effects. Moreover, the antimicrobial activity of Shikonin can play a great role in food and can also reduce the number of pathogenic bacteria in food. This paper summarizes the research on the pharmacological effects of Shikonin in recent years, as well as research on the mechanism of action of Shikonin in the treatment of certain skin diseases, to provide certain theoretical references for the clinical application of Shikonin, and also to provides research ideas for the investigation of the mechanism of action of Shikonin in other skin diseases.

Shikonin prevents mice from heat stroke-induced death via suppressing a trigger IL-17A on the inflammatory and oxidative pathways

Heat stroke (HS) is the deadliest disease. Due to the complex pathogenesis of HS, lack of effective therapeutic drugs for clinical treatment. Shikonin (SK) is the main active compound of Radix Arnebiae, which was evaluated on the HS model (temperature: (41 ± 0.5) ℃, relative humidity: (60 ± 5) %) via pathological and biochemical approaches in vivo and in vitro. Upon the dose of 10 mg.kg-1, SK delays the rising rate of core temperature, prolongs the survival time of mice, and improves organ injury and coagulation function markedly. Serum HS biomarkers interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) were decreased significantly by SK, which contribute to liver and lung protection in the models. Three pathways' responses to heat-stress were found to have a close connection with the IL-17 pathway via RNA sequencing and network analysis. WB and IHC results showed that the nuclear factor-κB (NF-κB) p65 in the SK group was down-regulated (P < 0.05). The expressions of nuclear factor erythroid 2 like 2 (NFE2L2/Nrf2) and heat shock protein 70 (HSP70) were up-regulated (P < 0.05). Additional administration of recombinant IL-17A protein on the HS model up-regulated the expression level of NF- κB p65 in the liver and lung tissue, additional intraperitoneal injection of IL-17A antibody in mice has a synergistic effect with SK in inhibiting tissue inflammatory response and protecting HS. In summary, SK was proved an effective compound for fulfilling the anti-inflammatory and antioxidative capacity of the HS model by reducing the production and inhibiting the expression of IL-17A.

Recent advances in shikonin for the treatment of immune-related diseases: Anti-inflammatory and immunomodulatory mechanisms

Shikonin, the primary active compound found in the rhizome of the traditional Chinese medicinal herb known as "ZiCao", exhibits a diverse range of pharmacological effects. This drug has a wide range of uses, including as an anti-inflammatory, antioxidant, and anti-cancer agent. It is also effective in promoting wound healing and treating autoimmune diseases such as multiple sclerosis, diabetes, asthma, systemic lupus erythematosus, inflammatory bowel disease, psoriasis, and rheumatoid arthritis. Although shikonin has a wide range of applications, its mechanisms are still not fully understood. This review article provides a comprehensive overview of the recent advancements in the use of shikonin for the treatment of immune-related diseases. The article also delves into the anti-inflammatory and immunoregulatory mechanisms of shikonin and offers insights into the inflammation and immunopathogenesis of related diseases. Overall, this article serves as a valuable resource for researchers and clinicians working in this field. These findings not only provide significant new information on the effects and mechanisms of shikonin but also establish a foundation for the development of clinical applications in treating autoimmune diseases.

The Renoprotective Effect of Shikonin in a Rat Model of Diabetic Kidney Disease

BACKGROUND

In diabetes mellitus, diabetic nephropathy (DN) is a typical complication and pivotal cause of chronic kidney disease. The DN disease burden is among the highest in the world and is associated with high morbidity, mortality, and disease burden. Safe and effective medications are urgently needed for the treatment of DN. Interest has been increasing in Shikonin, extracted from the naphthoquinone plant, particularly in determining its renal protective effect.

METHODS

In this study, we explored Shikonin's effects and potential mechanisms on a streptozotocin (STZ)-induced DN experimental model. An STZ-induced rat diabetic model was established, and the rats were treated with different doses of Shikonin (10/50 mg/kg) for 4 weeks. Blood, urine, and renal tissue samples were collected after the last administration. Renal tissues were examined to detect each group's physiologic, biochemical, histopathologic, and molecular changes.

RESULTS

The results showed that Shikonin administration could significantly alleviate the STZ-induced elevation of blood urea nitrogen, serum creatinine, urinary protein content, and renal pathologic injury. Furthermore, Shikonin significantly decreased oxidative stress, inflammation, and Toll-like receptor 4/myeloid differentiation primary response 88/nuclear factor-κB expression levels in DN kidney tissues. Shikonin showed a dose-dependent effect, with the best outcome at 50 mg/kg.

CONCLUSION

Shikonin could effectively alleviate DN-related nephropathy damage and reveal the underlying pharmacologic mechanism. Based on the results, a Shikonin combination can be used in clinical treatment.

Liangxue Jiedu Runzhi ointment in the treatment of mild and moderate psoriasis with blood-heat syndrome: A double-blind randomized controlled trial

INTRODUCTION

Psoriasis is a kind of chronic inflammatory skin disease characterized by erythema, skin hyperplasia, scales and keratinocyte hyperproliferation. Psoriasis Vulgaris, the most common kind of psoriasis, severely deteriorates the life quality of patients. Traditional Chinese Medicine (TCM) is a good choice for the treatment of psoriasis, which has been proved to be safe and effective, and may reduce the recurrence rate. In clinical practice, Liangxue Jiedu Runzhi (LJR) ointment can effectively treat mild and moderate psoriasis with blood-heat syndrome, but there is a lack of evidence-based medical evidence. This trial aims to evaluate the efficacy and safety of LJR ointment for the treatment of mild and moderate psoriasis with blood-heat syndrome.

METHODS

A multicenter, randomized, double-blind, placebo-controlled, and self-controlled clinical trial was carried out according to this paper. The symmetrical rashes of each subject were regarded as the target lesions and were randomly divided into a treatment group (LJR ointment group) and a control group (placebo group). The LJR ointment or placebo ointment were externally administered on bilateral symmetric rashes, twice a day for eight weeks. The follow-up examination was made for subjects every two weeks. The primary research finding was conveyed by Psoriasis Area and Severity Index (PASI) in 8 weeks. The secondary research finding includes adverse events.

RESULTS

46 subjects undergo this research project. The difference between PASI scores of the target lesions in the treatment group and control group is statistically significant were in 8 weeks (P < .001). The percentage of PASI 75 in treatment group and control group were 48% and 15% in week 8, respectively (x2 = 11.33, P < .05). No severe adverse events were reported.

CONCLUSIONS

LJR ointment was proved to have efficacy in the treatment of mild and moderate psoriasis with the blood-heat syndrome.

Molecular mechanisms of Biyu decoction as treatment for psoriasis: A network pharmacology and molecular docking study

BACKGROUND

The therapeutic effects of a combination of Chinese medicines called Biyu decoction have been clinically verified, although its molecular targets in psoriasis remain unknown.

AIM

To explore the molecular mechanisms of Biyu decoction for psoriasis treatment.

METHODS

In this network pharmacology and molecular docking study, the Traditional Chinese Medicine Systems Pharmacology database was searched for Biyu decoction active ingredients. GeneCards, Online Mendelian Inheritance in Man, PharmGkb, Therapeutic Target Database, and DrugBank databases were searched for psoriasis-related genes. The genes targeted by the decoction’s active ingredient and disease genes were intersected to obtain predictive targets of the drug during psoriasis treatment. Cytoscape 3.8.0 was used to construct a drug component/ target disease network. The The functional protein association networks database and Cytoscape were used to construct a protein-protein interaction network and streamline the core network. The Gene Ontology and Kyoto Encyclopedia of Genes and Genomes were used for pathway enrichment analysis. Molecular docking technology was used to verify the drug component/target disease network.

RESULTS

We screened 117 major active ingredients, including quercetin, kaempferol, naringenin, and acetyl-shikonin, and identified 213 gene targets, such as MAPK3, JUN, FOS, MYC, MAPK8, STAT3, and NFKBIA. Using a molecular docking analysis, the main active ingredients demonstrated good binding to the core targets. The Gene Ontology analysis showed that these ingredients were significantly associated with biological activities, such as transcription factor DNA binding, RNA polymerase II-specific DNA binding of transcription factors, and cytokine receptor binding; responses to lipopolysaccharides, molecules of bacterial origin, and oxidative stress; and were mainly distributed in membrane rafts, microdomains, and regions. The Kyoto Encyclopedia of Genes and Genomes analysis showed that decoction ingredients act on Th17 cell differentiation, tumor necrosis factor and mitogen-activated protein signaling pathways, the interleukin-17 signaling pathway, and the PI3K-Akt signaling pathway.

CONCLUSION

Biyu decoction may be effective against psoriasis through multi-component, multi-target, and multi-channel synergy.

Notch1/Hes1‑PTEN/AKT/IL‑17A feedback loop regulates Th17 cell differentiation in mouse psoriasis‑like skin inflammation

IL‑17A, the effector cytokine of T helper (Th) 17 cells, plays a crucial role in the pathogenesis of psoriasis. The Notch1 and PI3K/AKT signaling pathways are implicated in Th17 cell differentiation and IL‑17A production. The present study aimed to evaluate the regulatory effect of the Notch1/hairy and enhancer of split 1 (Hes1)‑PTEN/AKT/IL‑17A feedback loop on Th17 cell differentiation via the PI3K/AKT inhibitor LY294002 in a mouse model of psoriasis. Mice were randomly divided into 3 groups: a control group, a model group [5% imiquimod (IMQ)‑induced group] and an intervention group (5% IMQ‑induced plus LY294002‑treated group). Skin structural characteristics were recorded and evaluated by hematoxylin and eosin staining. The weights of the spleens and inguinal lymph nodes were measured. Th17 cell percentage, as well as the mRNA and protein expression levels of Notch1, Notch1 intracellular domain (NICD1), Hes1, PTEN, AKT, phosphorylated (p)‑AKT, mTOR complex 1 (mTORC1), p‑mTORC1, S6 kinase (S6K)1, S6K2 and IL‑17A were detected in skin samples of the three experimental groups. Additionally, splenic mononuclear cells from model mice were treated by 10 and 50 µM LY294002 to further evaluate its regulatory effect on Notch1/Hes1‑PTEN/AKT/IL‑17A feedback loop. Increased Th17 cell percentage, increased expression of Notch1, NICD1, Hes1, AKT, p‑AKT, mTORC1, p‑mTORC1, S6K1, S6K2 and IL‑17A, and decreased PTEN levels were observed in model mice alongside marked psoriasis‑like skin inflammation, splenomegaly and lymphadenopathy. LY294002 treatment significantly alleviated the severity of psoriasis‑like skin inflammation in the intervention mice, attenuated the degree of epidermal hyperplasia and dermal inflammatory cell infiltration, and mitigated splenomegaly and lymphadenopathy. In addition, LY294002 treatment reversed the increased Th17 cell percentage, as well as the increased expression of Notch1, NICD1, Hes1, AKT, p‑AKT, mTORC1, p‑mTORC1, S6K1, S6K2 and IL‑17A, and the decreased expression of PTEN. In vitro study from 5% IMQ‑induced mouse splenic mononuclear cells presented that high dose of LY294002 exerted more obviously regulatory effect on Notch1/Hes1‑PTEN/AKT/IL‑17A feedback loop. The current findings suggested that the Notch1/Hes1‑PTEN/AKT/IL‑17A feedback loop regulates Th17 cell differentiation within the disease environment of psoriasis. Blocking the Notch1/Hes1‑PTEN/AKT/IL‑17A feedback loop may thus be a potential therapeutic method for management of psoriatic inflammation.

C/EBPδ-induced epigenetic changes control the dynamic gene transcription of S100a8 and S100a9

The proinflammatory alarmins S100A8 and S100A9 are among the most abundant proteins in neutrophils and monocytes but are completely silenced after differentiation to macrophages. The molecular mechanisms of the extraordinarily dynamic transcriptional regulation of S100a8 and S100a9 genes, however, are only barely understood. Using an unbiased genome-wide CRISPR/Cas9 knockout (KO)-based screening approach in immortalized murine monocytes, we identified the transcription factor C/EBPδ as a central regulator of S100a8 and S100a9 expression. We showed that S100A8/A9 expression and thereby neutrophil recruitment and cytokine release were decreased in C/EBPδ KO mice in a mouse model of acute lung inflammation. S100a8 and S100a9 expression was further controlled by the C/EBPδ antagonists ATF3 and FBXW7. We confirmed the clinical relevance of this regulatory network in subpopulations of human monocytes in a clinical cohort of cardiovascular patients. Moreover, we identified specific C/EBPδ-binding sites within S100a8 and S100a9 promoter regions, and demonstrated that C/EBPδ-dependent JMJD3-mediated demethylation of H3K27me₃ is indispensable for their expression. Overall, our work uncovered C/EBPδ as a novel regulator of S100a8 and S100a9 expression. Therefore, C/EBPδ represents a promising target for modulation of inflammatory conditions that are characterized by S100a8 and S100a9 overexpression.

Evidence and Potential Mechanism of Action of Lithospermum erythrorhizon and Its Active Components for Psoriasis

Background: Traditional Chinese medicine is effective in the treatment of psoriasis and can significantly reduce skin inflammation and psoriatic lesions with minimal side effects. Shikonin (SHI) and β,β-dimethylacryloyl alkannin (DMA), the main active components of Lithospermum erythrorhizon, have strong anti-inflammatory effects. This systematic review aimed to evaluate the efficacy and safety of Lithospermum erythrorhizon and its main active components and to elucidate the potential mechanisms of their action in psoriasis treatment.

Methods: PubMed, Embase, Cochrane Central Register of Controlled Trials, China National Knowledge Infrastructure, Chinese Scientific Journals, Wan Fang, and Chinese Biomedicine databases were systematically searched for articles published between 1 January 1970, and 31 February 2021. We included clinical and preclinical studies that examined the effects of Lithospermum erythrorhizon and its active components on psoriasis. All data were analyzed using RevMan 5.3 software. The Cochrane and SYRCLE’s risk-of-bias tools were used to assess the quality of all studies.

Results: Eleven clinical trials including 1024 participants and 23 preclinical studies were assessed. Meta-analysis showed that when treating patients with psoriasis, the Chinese herbal medicine (CHM) formulas with Lithospermum erythrorhizon as the sovereign herb can significantly improve psoriatic dermatitis, which can significantly reduce the psoriasis area and severity index (PASI) score (mean difference [MD] = -2.00, 95% confidence interval [CI] [-3.19, -0.80], p = 0.001; I² = 85%). The incidence rates of diarrhea (risk ratio = 0.21, 95% CI [0.06, 0.81], p = 0.02) were higher in the CHM formulas group than in the control group, whereas other adverse events were not significantly different between the two groups (p > 0.05). We evaluated the PASI score of mice on day 7 and found that SHI and DMA also alleviated psoriatic lesions (MD = -3.36, 95% CI [-4.67, -2.05], p < 0.00001, I² = 94%). Furthermore, the epidermal thickness decreased more after SHI or DMA treatment than in the control group (MD = -34.42, 95%CI [-41.25, -27.59], p < 0.00001, I² = 93%). Based on preclinical studies, we also summarized and mapped the mechanisms of SHI and DMA in the treatment of psoriasis.

Conclusion: Available findings demonstrated that Lithospermum erythrorhizon combined with other conventional treatments is useful in treating psoriasis. Preclinical evidence has shown that the active components of Lithospermum erythrorhizon exhibit a potential anti-inflammatory effect, promote keratinocyte apoptosis, inhibit keratinocyte proliferation and angiogenesis, and block the cell cycle. In summary, our findings suggest that Lithospermum erythrorhizon and its active components can be used to treat psoriasis.

Shikonin combined with methotrexate regulate macrophage polarization to treat psoriasis

This study aimed to investigate whether shikonin combined with methotrexate could inhibit psoriasis progression by regulating the polarization of macrophages through in vivo and in vitro experiments. Imiquimod was administrated to the exposed skin of BALB/c mice, and shikonin and methotrexate suspension were also given by gavage. The erythema, scales and thickness were scored for mice lesions in each group, and the total score was obtained by adding the above three scores, and calculated as psoriasis area and severity index (PASI) score. The skin lesion tissue from mice was isolated and used for hematoxylin-eosin staining and immunohistochemistry assay. Drug-containing serum was prepared and administrated into mouse macrophage RAW264.7 cells, followed by simulation of LPS. The levels of tumor necrosis factor-α (TNF-α), Interleukin (IL)-1β, and IL-6 in cell supernatant were assessed using ELISA Kits and real-time PCR. In imiquimod-induced psoriasis mice, shikonin combined with methotrexate exerted protective effects by reducing erythema and PASI scores, decreasing backer score and epidermal thickness, and particularly regulating macrophage polarization. In LPS-stimulated RAW264.7 cells, shikonin combined with methotrexate regulated M1/M2 polarization and altered the levels of M1 markers. Shikonin combined with methotrexate inhibit psoriasis progression by regulating the polarization of macrophages, which may be useful in the treatment of psoriasis.

Gene Expression Meta-Analysis of Potential Shared and Unique Pathways between Autoimmune Diseases under Anti-TNFα Therapy

While anti-TNFα has been established as an effective therapeutic approach for several autoimmune diseases, results from clinical trials have uncovered heterogeneous patients' response to therapy. Here, we conducted a meta-analysis on the publicly available gene expression cDNA microarray datasets that examine the differential expression observed in response to anti-TNFα therapy with psoriasis (PsO), inflammatory bowel disease (IBD) and rheumatoid arthritis (RA). Five disease-specific meta-analyses and a single combined random-effects meta-analysis were performed through the restricted maximum likelihood method. Gene Ontology and Reactome Pathways enrichment analyses were conducted, while interactions between differentially expressed genes (DEGs) were determined with the STRING database. Four IBD, three PsO and two RA datasets were identified and included in our analyses through our search criteria. Disease-specific meta-analyses detected distinct pro-inflammatory down-regulated DEGs for each disease, while pathway analyses identified common inflammatory patterns involved in the pathogenesis of each disease. Combined meta-analyses further revealed DEGs that participate in anti-inflammatory pathways, namely IL-10 signaling. Our analyses provide the framework for a transcriptomic approach in response to anti-TNFα therapy in the above diseases. Elucidation of the complex interactions involved in such multifactorial phenotypes could identify key molecular targets implicated in the pathogenesis of IBD, PsO and RA.

Therapeutic Effects of Shikonin on Skin Diseases: A Review

Shikonin is one of the primary active components extracted from the dried root ofZicao (Lithospermum erythrorhizon, Onosma paniculata, or Arnebia euchroma), a traditional Chinese herbal medicine. Shikonin is known to not only exert anti-proliferative, anti-inflammatory, and anti-angiogenic activities, but also play a crucial role in triggering the production of reactive oxygen species, suppressing the release of exosomes, and inducing apoptosis. Increasing evidence suggests that shikonin has a protective effect against skin diseases, including psoriasis, melanoma, and hypertrophic scars. In order to evaluate the application potential of shikonin in the treatment of skin diseases, this review is the first of its kind to provide comprehensive and up-to-date information regarding the uses of shikonin and its derivatives on skin diseases and its underlying mechanisms. In this review, we have focused on the signaling pathways and cellular targets involved in the anti-dermatosis effects of shikonin to bridge the gaps in the literature, thereby providing scientific support for the research and development of new drugs from a traditional medicinal plant.

Shikonin, a naphthalene ingredient: Therapeutic actions, pharmacokinetics, toxicology, clinical trials and pharmaceutical researches

BACKGROUND

Shikonin is one of the major phytochemical components of Lithospermum erythrorhizon (Purple Cromwell), which is a type of medicinal herb broadly utilized in traditional Chinese medicine. It is well established that shikonin possesses remarkable therapeutic actions on various diseases, with the underlying mechanisms, pharmacokinetics and toxicological effects elusive. Also, the clinical trial and pharmaceutical study of shikonin remain to be comprehensively delineated.

PURPOSE

The present review aimed to systematically summarize the updated knowledge regarding the therapeutic actions, pharmacokinetics, toxicological effects, clinical trial and pharmaceutical study of shikonin.

METHODS

The information contained in this review article were retrieved from some authoritative databases including Web of Science, PubMed, Google scholar, Chinese National Knowledge Infrastructure (CNKI), Wanfang Database and so on, till August 2021.

RESULTS

Shikonin exerts multiple therapeutic efficacies, such as anti-inflammation, anti-cancer, cardiovascular protection, anti-microbiomes, analgesia, anti-obesity, brain protection, and so on, mainly by regulating the NF-κB, PI3K/Akt/MAPKs, Akt/mTOR, TGF-β, GSK3β, TLR4/Akt signaling pathways, NLRP3 inflammasome, reactive oxygen stress, Bax/Bcl-2, etc. In terms of pharmacokinetics, shikonin has an unfavorable oral bioavailability, 64.6% of the binding rate of plasma protein, and enhances some metabolic enzymes, particularly including cytochrome P450. In regard to the toxicological effects, shikonin may potentially cause nephrotoxicity and skin allergy. The above pharmacodynamics and pharmacokinetics of shikonin have been validated by few clinical trials. In addition, pharmaceutical innovation of shikonin with novel drug delivery system such as nanoparticles, liposomes, microemulsions, nanogel, cyclodextrin complexes, micelles and polymers are beneficial to the development of shikonin-based drugs.

CONCLUSIONS

Shikonin is a promising phytochemical for drug candidates. Extensive and intensive explorations on shikonin are warranted to expedite the utilization of shikonin-based drugs in the clinical setting.