Mechanism of asiatic acid in relieving psoriasis by modulating the PI3K/Akt/NF-κB pathway and NLRP3 inflammasome

Abstract

Objective:

The purpose of this paper is to expound the effect of asiatic acid (AA) on psoriasis via modulating the PI3K/Akt/NF-κB pathway and NLRP3 inflammasome.

Methods:

An imiquimod (IMQ)-induced psoriasis model in BALB/c mice was established. Mice were divided into the control, IMQ, and AA treatment groups with different doses. Psoriasis area and severity were scored using the Psoriasis Area Severity Index (PASI). Histological changes, inflammatory factor levels in skin lesions, and expressions of NLRP3 inflammasome-related proteins and pathway proteins were measured. For cellular experiments, HaCaT cells were classified into control, model, AA low and high concentration groups, and AA-H + IGF group. Cells were stimulated with IL-17A, IL-22, TNF-α, IL-1α, and OSM (M5) to induce psoriasis-like conditions, followed by treatment with AA or IGF. Cell viability, oxidative stress levels, inflammatory factors, NLRP3 expression, and PI3K/Akt/NF-κB pathway protein levels were assessed.

Results:

In vivo, IMQ-induced mice showed psoriasis-like symptoms, including increased PASI scores, IL-6, TNF-α, IL-17A, and NLRP3-related protein levels. AA treatment alleviated these symptoms, reducing NLRP3, apoptosis-associated speck-like protein containing a CARD (ASC), and Caspase-1 expression, and restraining the PI3K/Akt/NF-κB pathway phosphorylation. In cellular experiments, M5 induction impeded cell viability and advanced oxidative stress, IL-1β, IL-6, and NLRP3 expression, activating the PI3K/Akt/NF-κB pathway. AA markedly reversed these change.

Conclusion:

AA alleviates psoriasis symptoms by blocking the PI3K/Akt/NF-κB pathway and NLRP3 inflammasome.

Graphical Abstract

Keywords

Psoriasis asiatic acid PI3K/Akt/NF-κB pathway NLRP3 inflammasome imiquimod phosphorylation

Introduction

Psoriasis is a chronic, immune-mediated skin disorder that affects millions of people worldwide. It exhibits a distinctive feature of accelerated skin cell renewal, resulting in the development of thickened, scaly patches on the epidermis,¹ and exists in various forms, including plaque, flexural, guttate, pustular, and erythrodermic.² Current approaches to treating psoriasis encompass topical medications, light therapy, systemic immune-modulating drugs, and biological agents.³ However, due to its complex pathogenesis that involves the activation of immune cells, oxidative stress, and the dysregulation of inflammatory signaling pathways,^4,5 challenges still remains in the therapy of psoriasis.

Among the critical molecular mechanisms involved, the PI3K/Akt/NF-κB pathway and the NLRP3 inflammasome play pivotal roles in the initiation and progression of inflammation in psoriasis.^6,7 The PI3K/Akt/NF-κB pathway is a critical signaling pathway that regulates cellular responses to stress, inflammation, and immune activation.⁸ In psoriasis, this pathway is often overactivated, leading to increased inflammatory responses and skin cell proliferation. The NLRP3 inflammasome is a protein complex that plays a central role in the activation of the innate immune system⁹ and is responsible for processing and releasing pro-inflammatory cytokines.¹⁰ These pathways contribute to the inflammatory microenvironment in the skin, which is a hallmark of the disease. Targeting these pathways has become a promising approach to modulate the inflammatory response and alleviate symptoms.

Asiatic acid (AA), a bioactive compound isolated from Centella Asiatica, has garnered attention due to its potent anti-inflammatory, antioxidant, and wound-healing properties.^11,12 AA has the ability to regulate various signaling pathways involved in inflammatory diseases,¹³ including its effects on oxidative stress and immune responses. It has exhibited an effect against psoriasis by regulating the IL-17A and IL-23 pathways.¹⁴ Despite its known therapeutic properties, the specific role of AA in modulating the PI3K/Akt/NF-κB pathway and NLRP3 inflammasome in the context of psoriasis remains largely uncovered.

This research is designed to explore the potential of AA in ameliorating psoriasis symptoms by targeting these critical molecular pathways. The experimental approach involves using an imiquimod (IMQ)-induced psoriasis mouse model to assess the effects of AA on psoriasis-like skin lesions. Additionally, the expression of proteins involved in the PI3K/Akt/NF-κB pathway and NLRP3 inflammasome will be analyzed to elucidate the molecular mechanisms by which AA exerts its therapeutic effects. Through these investigations, the study is going to provide new insights into the therapeutic potential of AA for psoriasis treatment.

Materials and methods

Ethics statement

This experiment was assented by the Laboratory Animal Ethics Committee of Xiamen Changgung Hospital Unit.

Grouping and animal model preparation

Fifty SPF-grade male BALB/c mice (aged 4–6 weeks, weighing 20 ± 2 g) were purchased from Hangzhou Ziyuan Experimental Animal Technology Co., Ltd. Only male mice were selected for this study to minimize potential interference from the female estrous cycle and sex hormones (such as estrogen) on immune responses and inflammatory signaling pathways, thereby reducing experimental variability in the animal model. The mice were allowed free access to food and water under conditions of 22 ± 1°C temperature, 55 ± 2% relative humidity, and a 12-h light/dark cycle. After 3 days of acclimatization, they were randomly divided into the Control group, IMQ group, and AA groups at different doses (25 and 100 mg/kg), with 10 mice in each group. The backs of the mice in all groups were shaved. Except for the Control group, mice in the other groups were treated with a fixed daily dose of 62.5 mg of 5% IMQ cream (99011-02-6, Yeasen Biotechnology (Shanghai) Co., Ltd.) applied to their backs for 7 consecutive days. Starting from the second day of modeling, AA (464-92-6, Chengdu Yijierui Biotechnology Co., Ltd., purity ≥98.0%) was administered orally at doses of 25 and 100 mg/kg once daily. Mice in the Control and IMQ groups were gavaged with the same volume of saline. After 7 days, blood was collected from the retro-orbital venous plexus, and the mice were then euthanized by cervical dislocation. The skin of the mice was subsequently harvested for further experiments.

Evaluation of skin lesion index

The Psoriasis Area and Severity Index (PASI) score was implemented to assess the skin lesion index in each group of mice. After modeling, mice were photographed daily to record the changes of skin lesions. Three dimensions of erythema, scaling, and infiltration at the skin lesions were evaluated. Each dimension was divided into 0-4 according to the severity (0 indicates none; 1 represents mild; 2 signifies moderate; 3 denotes severe; and 4 indicates very severe), and then the sum of the three scores was calculated to obtain the overall PASI score.

Hematoxylin-eosin (HE) staining

The newly acquired skin lesion tissue was initially immobilized in a 4% paraformaldehyde solution, then the steps of dehydration, embedding, sectioning, and dewaxing were carried out sequentially. Subsequently, the sections underwent staining with hematoxylin solution (D006, Jianjian Bioengineering Institute, Nanjing, China), and then immersed in eosin solution for 3 min. At the end of the staining process, the sections were dehydrated by ethanol gradient and cleared with xylene, followed by blocking with neutral gum. Finally, the pathological changes of the skin lesions were carefully inspected under a microscope (Carl Zeiss, Germany).¹⁵

Cell culture and grouping

HaCaT cells are a spontaneously immortalized human keratinocyte cell line widely used in psoriasis research. HaCaT cells (P-X723, Bohu Biotechnology, Shanghai, China) were maintained in DMEM encompassing 10% FBS together with 100 U/mL penicillin-streptomycin (c125c5, NCM Biotech, Suzhou, China), and incubated at 37℃ with 5% CO2. HaCaT cells were grouped into control, model (M5, stimulated with a mixed cytokine cocktail of IL-17A, IL-22, TNF-α, IL-1α, and OSM), AA low and high concentration (AA-L, AA-H), and AA-H + PI3K/Akt activator insulin-like growth factor I (AA-H + IGF-I) groups. All groups, except the control group, established an in vitro psoriatic keratinocyte model by using 2.5 ng/mL of M5 mixture (IL-17A, IL-22, TNF-α, IL-1α, OSM, Sino Biological, Beijing, China) to stimulate HaCaT cells for 12 h. The AA-L (5 μg/mL) and AA-H (20 μg/mL) groups were subjected to 48-h treatment with corresponding concentrations of AA in HaCaT cells, followed by 12-h treatment with M5. Cells in the AA-H + IGF-I group were pretreated for 12 h with 13 ng/mL of IGF-I (291-G1, R&D Systems, Inc., USA), followed by 12-h treatment with 20 μg/mL of AA in HaCaT cells, and then received 12-h M5 treatment.^16–18

Cell counting kit-8 (CCK-8) assay

HaCaT cells were seeded into 96-well microplates at 1 × 10⁴ cells/mL. After the cells underwent logarithmic growth, they were grouped as previously described above. The group of HaCaT cells cultured under normal culture conditions served as the control group, and blank wells, without any cells, was also incubated. Each well was subsequently treated with 10 μL of CCK-8 reagent (HY-K0301, MedChemExpress, USA) at 37℃ for 4 h. The absorbance (D) of each well was measured at 450 nm to calculate the cell viability: cell viability (%) = [(D_{drug-treated group} − D_{blank wells})/(D_{control group} − D_{blank well})] × 100%.¹⁹

Measurement of reactive oxygen species (ROS)

HaCaT cells were subjected to 30-min incubation with 5 µmol/mL Cell Rox probe (C10444, Thermo Fisher Scientific, USA) at 37°C under dark conditions, then the probe was discarded and the cells were immobilized using paraformaldehyde (4%, 15 min), followed by 15-min staining with DAPI (1 µg/mL) in the dark. Finally, the cells were treated with anti-fluorescence quenching agent and captured by fluorescence microscope (Olympus Corporation, Japan). ImageJ software was utilized to measure the average fluorescence intensity.²⁰

Measurement of superoxide dismutase (SOD) and glutathione (GSH) levels

GSH activity in the cells was assessed using a kit (CS0260, Sigma-Aldrich, USA). HaCaT cells underwent PBS washing followed by the addition of a 5% salicylic acid solution. After centrifugation (20 min, 16,000 × g), the supernatant was mixed with 150 μL of GSH mixture for 5-min incubation and 50 μL of diluted NADPH solution for 20 min-incubation. Absorbance at 412 nm was determined using a microplate spectrophotometer.

HaCaT cells were homogenized in ice-cold 0.1 M PBS (pH 7.4), and then the homogenate was filtered. The resulting supernatant was centrifuged using a refrigerated centrifuge at 4°C (20 min, 16,000 × g), which was assayed for SOD enzyme activity by an SOD kit (S0086, Beyotime, Shanghai, China).²¹

ELISA

Serum was attained from mouse peripheral blood by 15-min centrifugation at 1000 × g. Serum concentrations of IL-17A, IL-1β, and IL-6 were quantified using the Mouse IL-17A Kit (KE10020, Proteintech, Wuhan, China), the Mouse IL-1β Kit (KE10003, Proteintech), and the Mouse IL-6 Kit (KE10007 , Proteintech), respectively. The treated cells were subjected to 10-min centrifugation at 3500 r/min. After that, the supernatant was extracted, and the concentrations of IL-1β and IL-6 in the supernatant were quantified using the Human IL-1β Kit (E-EL-H0149, Elite Bioscienc, Wuhan, China) and the Human IL-6 Kit (E-HSEL-H0003, Elite Bioscience). Absorbance at 450 nm was estimated using a microplate reader (Heales, China).¹⁷

Western blot

Cells and tissues were lysed in buffer (AWB0136, Abiowell, Hunan China) at 4°C for 20 min, followed by 15-min centrifugation at 14,000 rpm. Protein (15 μg) was separated by 12% SDS-PAGE and transferred to a PVDF membrane (88520, Thermo Fisher Scientific). After 2-h blocking in 5% milk, the membrane was subjected to incubation overnight with primary antibodies: PI3K (1:1000, 4255, Cell Signaling Technology [CST], USA), Akt (1:1000, 9271, CST), NF-κB (1:1000, 8242, CST), p-PI3K (1:1000, 4249, CST), p-Akt (1:1000, 9271, CST), p-NF-κB (1:1000, 3033, CST), and GAPDH (1:1000, ab8245, Abcam, UK) at 4°C. After washing, the membrane was subjected to 2-h incubation with secondary antibody (1:5000, ab6721, Abcam). Proteins were detected using chemiluminescent substrate (Abiowell) and visualized with ChemiScope 6000 (CLINX, China). Band quantification was performed using ImageJ software.¹⁷

RT-qPCR

Total RNA samples were isolated from the cells using Trizol reagent (15596026, Thermo Fisher Scientific). Subsequently, mRNA was reverse transcribed to cDNA using the mRNA reverse transcription kit (CW2569, CWBIO, China). RT-qPCR was performed in the CFX96 Touch™ Real-Time PCR detection system (Bio-Rad, USA) using the SYBR Green PCR premix kit. GAPDH functioned as an internal control. The 2^−ΔΔCt approach was employed for data analysis. The primer sequences of the genes are presented in Table 1.²²

Table 1.

Primer sequences for genes.

Primer sequence	Forward	Reverse
ASC (human)	5'-CCTCAGTCGGCAGCCAAG-3'	5'-TCCTCCACCAGGTAGGACTG-3'
Caspase-1 (human)	5'-GAGAGAAAAGCCATGGCCGA-3'	5'-ACGTGCTGTCAGAGGTCTTG-3'
NLRP3 (human)	5'-CGCTTCGGCAGCACATATAC-3'	5'-CTGTGTCACAAGGCTCACCT-3'
GAPDH (human)	5'-AATGGGCAGCCGTTAGGAAA-3'	5'-GCGCCCAATACGACCAAATC-3'
ASC (mice)	5'-GACAGTGCAACTGCGAGAAG-3'	5'-GCAATGAGTGCTTGCCTGTG-3'
Caspase-1 (mice)	5'-GGCACATTTCCAGGACTGACTG-3'	5'-GCAAGACGTGTACGAGTGGTTG-3'
NLRP3 (mice)	5'-CAAGGCTGCTATCTGGAGGAAC-3'	5'-CCTTTCTCGGGGCGGGTAATC-3'
GAPDH (mice)	5'-GCCTCCTCCAATTCAACCCT-3'	5'-TACGGCCAAATCCGTTCACA-3'

Statistics

All data are presented as mean ± standard deviation (SD). Comparisons among three or more groups were performed using one-way analysis of variance (ANOVA), followed by Tukey’s post hoc test for pairwise comparisons. All experiments were repeated three times. A p-value <0.05 was considered statistically significant. All tests were conducted using GraphPad software version 8.0.

Results

AA improves skin lesions in psoriasis-like mice

To investigate the effects of AA on psoriasis-like mice, we established an IMQ-induced psoriasis-like BALB/c mouse model and administered AA at doses of 25 or 100 mg/kg via oral gavage (i.g.) from days 2 to 7, followed by sampling and testing after 7 days (Figure 1(a)). IMQ-treated mice had erythema, scaling and slightly thickened lesions with notably higher PASI scores (p < 0.001). Treatment with 25 and 100 mg/kg of AA improved erythema and scaling, and infiltration in the dorsal lesions of IMQ mice, reducing PASI scores (p < 0.01) (Figure 1(b)). These results reflect that IMQ ointment induced psoriasis-like skin lesions, and AA treatment alleviated these lesions. HE staining indicated that IMQ-treated mice showed keratosis, an enlarged stratum corneum, a thinned granular layer, and hypertrophied stratum spinosum, resembling human psoriasis. AA treatment (25 and 100 mg/kg) improved these histopathological changes, restoring the skin structure in IMQ-treated mice (Figure 1(c)).

Figure 1.

AA improves skin lesions in psoriasis-like mice. (a) Schematic diagram of the in vivo experimental procedure; (b) PASI scores of mice in each group; (c) Histopathological morphology of skin lesions in mice from each group observed by HE staining at 200× magnification, scale bar = 100 μm. Data are presented as mean ± SD; n = 10. Compared with the Control group, ^###p < 0.001; compared with the IMQ group, **p < 0.01.

AA improves inflammation levels in skin lesion tissues of psoriasis-like mice

Subsequently, we used ELISA to estimate the inflammatory factors levels in mice serum. It was revealed that IMQ-treated mice exhibited higher levels of IL-6, IL-1β, and IL-17A, whereas treatment with 25 and 100 mg/kg of AA reduced these inflammatory factors expressions in IMQ-treated mice (Figure 2(a)–(c)).

Figure 2.

AA improves inflammation levels in skin lesion tissues of psoriasis-like mice. ELISA kits were used to detect the levels of IL-6 (A), IL-1β (B), and IL-17A (C) in the serum of mice in each group. Data are expressed as mean ± SD; n = 5. ^###p < 0.001 versus the control group; *p < 0.05 and ***p < 0.001 versus the IMQ group.

AA inhibits NLRP3 inflammasome expression and PI3K/Akt/NF-κB pathway phosphorylation in psoriasis-like skin lesions

RT-qPCR showed that poptosis-associated speck-like protein containing a CARD (ASC), Caspase-1, and NLRP3 mRNA levels were notably increased after IMQ treatment, while AA (25 and 100 mg/kg) reduced these levels (Figure 3(a)), revealing inhibition of NLRP3 inflammasome expression. Western blot analysis revealed elevated p-PI3K, p-Akt, and p-NF-κB expression in IMQ-treated mice, which was noticeably reduced by AA treatment (25 and 100 mg/kg) (Figure 3(b)), underscoring that suppression of the PI3K/Akt/NF-κB pathway phosphorylation in the skin lesion tissues of psoriasis-like mice.

Figure 3.

AA inhibits NLRP3 inflammasome expression and PI3K/Akt/NF-κB pathway phosphorylation in skin lesion tissues of psoriasis-like mice. (a) RT-qPCR was performed to detect the expression of NLRP3 inflammasome-associated ASC, Caspase-1 and NLRP3 mRNA in the skin tissues of mice in each group; (b) Western blot was performed to measure the expression of PI3K/Akt/NF-κB pathway-associated proteins in the skin tissues of mice in each group. Data are expressed as mean ± SD; n = 5. ^###p < 0.001 versus the control group; *p < 0.05, **p < 0.01, and ***p < 0.001 versus the IMQ group.

AA impedes M5-induced HaCaT cell activity, inflammation, and oxidative stress

At the animal level, we observed that AA could block the phosphorylation of the PI3K/Akt/NF-κB pathway. At the cellular level, we introduced the pathway activator IGF to further verify the mechanism. HaCaT cells were grouped into the control, M5, AA-L, AA-H, and AA-H + IGF groups (Figure 4(a)). CCK-8 assays demonstrated that M5 induction markedly enhanced cell viability, while AA (5 and 20 μg/mL) impeded M5-induced cell activity, with further activation of the PI3K/Akt/NF-κB pathway by IGF reversing this effect (Figure 4(b)). Subsequently, ELISA revealed elevated IL-1β and IL-6 levels in the M5 group, which were remarkably reduced in the AA-treated groups. IGF addition reversed the inhibitory impact of AA on IL-1β and IL-6 (Figure 4(c)). Oxidative stress assays presented increased ROS and decreased GSH and SOD in the M5 group, which were restored by AA treatment. The AA-H + IGF group exhibited elevated ROS and decreased GSH and SOD relative to the AA-H group (Figure 4(d)).

Figure 4.

AA inhibits M5-induced inflammation and oxidative stress in HaCaT cells. (a) Flowchart of AA treatment on HaCaT cells in vitro; (b) Cell viability detected by CCK8 assay; (c) Expression of inflammatory cytokines IL-1β and IL-6 in cells detected by ELISA; (d) Levels of ROS, GSH, and SOD detected by relevant kits. Data are presented as mean ± SD; N = 3. Compared with the Control group, ^###p < 0.001; compared with the IMQ group, **p < 0.01, ***p < 0.001; compared with the AA-H group, ^$$$p < 0.001.

AA restrains NLRP3 inflammasome expression and PI3K/Akt/NF-κB pathway phosphorylation in M5-induced HaCaT cells

RT-qPCR results indicated that M5 notably induced ASC, Caspase-1, and NLRP3 mRNA expression in HaCaT cells, while AA (5 and 20 μg/mL) effectively suppressed these expressions. Addition of IGF activated these mRNA expressions (Figure 5(a)). Western blot results suggested that M5 induced p-PI3K, p-Akt, and p-NF-κB expression, which was obviously impeded by AA (5 and 20 μg/mL). IGF further activated these pathways (Figure 5(b)).

Figure 5.

AA suppressess M5-induced NLRP3 inflammasome expression and PI3K/Akt/NF-κB pathway phosphorylation in HaCaT cells. (a) RT-qPCR was performed to test the expression of NLRP3 inflammasome-related ASC, Caspase-1 and NLRP3 mRNA in the cells; (b) Western blot was performed to examine the expression of PI3K/Akt/NF-κB pathway-related proteins in the cells. Data were expressed as mean ± SD; n = 3. ^##p < 0.01 and ^###p < 0.001 versus the control group; *p < 0.05, **p < 0.01, and ***p < 0.001 versus the IMQ group; ^$$p < 0.01 and ^$$$p < 0.001 versus the AA-H group.

Discussion

Psoriasis can occur at any age, causing a substantial impact on both individuals and society.²³ Asiatica is a renowned traditional herb praised for its advantageous effects on skin health and the healing of wounds.²⁴ This study delved into the impact of AA on psoriasis through its modulation of the PI3K/Akt/NF-κB pathway and NLRP3 inflammasome. Our findings offer significant insights into the potential therapeutic mechanisms of AA in ameliorating psoriasis symptoms.

Specifically, AA was found to markedly reduce the severity of skin lesions, decrease the levels of pro-inflammatory cytokines, and block the activation of key molecular pathways associated with inflammation, including the PI3K/Akt/NF-κB pathway and NLRP3 inflammasome. Similar results were obtained in research done by Moon GH et al., which suggests that AA treatment in atopic dermatitis reduces inflammation-related genes by down-regulating NF-κB and MAPK pathways.¹⁸ The anti-inflammatory effect of AA through the AMPK/PI3K/AKT pathway was also observed by Liu N et al.²⁵ These findings suggest that AA may serve as a promising therapeutic agent for psoriasis, with effects likely mediated by modulating immune responses and oxidative stress.

The clinical improvement observed was consistent with the downregulation of inflammatory cytokines such as IL-6, IL-1β, and IL-17A. These cytokines play crucial roles in the pathogenesis of psoriasis, as they are involved in the activation of immune cells^26,27 and the promotion of skin cell proliferation.²⁸ Gertel S et al. have explored that IL-6, IL-1β, and IL-17A are highly elevated in the serum and skin lesions of psoriasis patients.²⁹ This also be observed in animal model established in the study done by Surcel M et al.³⁰ AA’s anti-inflammatory properties may be ascribed to its ability to suppress the production of these cytokines. In particular, IL-17A is a critical cytokine in psoriasis,³¹ driving the expression of other pro-inflammatory cytokines and promoting the infiltration of T helper 17 cells into the skin.³² By inhibiting IL-17A and other cytokines, AA may disrupt this inflammatory cascade, ultimately reducing skin lesions.

The involvement of the PI3K/Akt/NF-κB pathway in psoriasis pathogenesis has been well documented.^15,33 This study reflects that AA inhibited the phosphorylation of key proteins in this pathway. This is consistent with previous research indicating that the PI3K/Akt/NF-κB pathway plays a pivotal role in the regulation of immune responses³⁴ and inflammation.³⁵ Activation of this pathway leads to the expression of pro-inflammatory cytokines and chemokines, as well as the proliferation of keratinocytes. Inhibition of this pathway by AA may explain the reduction in inflammatory cytokines and skin lesions observed in the treated mice. Additionally, the suppression of PI3K/Akt/NF-κB signaling by AA could also contribute to its antioxidant effects, as this pathway is involved in the regulation of oxidative stress,³⁶ a crucial factor in the development of psoriasis.³⁷

NLRP3 inflammasome is another critical component in the inflammatory response associated with psoriasis. In this study, AA treatment greatly reduced the expression of NLRP3 inflammasome components, including NLRP3, ASC, and Caspase-1. This is in line with previous studies that have suggested that NLRP3 activation is a key driver of inflammation in psoriasis and other chronic inflammatory diseases.^38,39 The NLRP3 inflammasome triggers the formation and release of mature IL-1β and IL-18,⁴⁰ which further amplify the inflammatory response in psoriasis.⁴¹ By inhibiting NLRP3 activation, AA may reduce the excessive production of IL-1β and IL-18, thereby alleviating inflammation and tissue damage in the skin. The inhibition of NLRP3 by AA also supports its role as an anti-inflammatory and antioxidant agent, as the activation of NLRP3 inflammasome is closely linked to the generation of ROS⁴² and oxidative stress.

At the cellular level, AA was found to exert a protective effect on HaCaT keratinocytes, which are commonly used to model psoriasis. AA not only improved cell viability but also reduced oxidative stress, as evidenced by lower levels of ROS and higher levels of antioxidant markers such as SOD and GSH. This finding is consistent with the well-established antioxidant properties of AA, which has been shown to scavenge free radicals⁴³ and reduce oxidative damage in various cell types.⁴⁴ The reduction in oxidative stress could be a key factor in the overall therapeutic effects of AA, as oxidative stress is known to contribute to the activation of inflammatory pathways, including the PI3K/Akt/NF-κB pathway and NLRP3 inflammasome.^45,46

In conclusion, this study demonstrates that AA ameliorates psoriasis symptoms by inhibiting the PI3K/Akt/NF-κB pathway and NLRP3 inflammasome activation. By targeting both the immune system and oxidative stress pathways, AA has the potential to become an important therapeutic agent in the clinical management, which has a profound impact on the quality of life for many patients. However, further researches with lager samples are required to verify the results of this study and fully elucidate the mechanisms underlying its effects, as well as to confirm its clinical efficacy and safety in long-term use.

Footnotes

Declaration of Conflicting Interests

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by Science and Technology Commission of Xiamen, Xiamen Science and Technology Beneficiay Foundation Project (No. 3502Z20214ZD123).

ORCID iD

Mengzhuang Liu

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