Preparation and characterization of intelligent and active bi-layer film based on carrageenan/pectin for monitoring freshness of salmon.

This work aimed to develop and characterize a novel bi-layer film (BIF) for monitoring the freshness of salmon. The indicator layer consists of carrageenan (Car), pectin (PEC) and purple sweet potato anthocyanin (PSPA), and the antibacterial layer consists of Car and magnolol (Mag). The results showed that the Car/Mag2 had the optimal water resistance: the static water contact angle of 80.36 ± 0.92 °, moisture content of 31.38 ± 0.86 %, swelling degree of 92.96 ± 0.46 %, and water solubility of 40.08 ± 1.17 %, and showed excellent antibacterial properties against E. coli and S. aureus with antibacterial rate of 86.13 % ± 0.10 % and 97.53 % ± 0.02 %, respectively. Then BIFs with different PSPA concentration were tested. The morphology, mechanical and water vapor properties (WVP) of the BIFs were studied, and its application in salmon preservation was evaluated. The mechanical properties and WVP test results showed that the BIF0.2 had the optimal Tensile strength (TS) and WVP values. The BIFs showed distinguishable color changes between the pH ranges of 3-10. The shelf life of salmon packaged by BIF0.2 was prolonged by 2 days. Moreover, the BIF0.2 was able to effectively monitor salmon freshness. In conclusion, the BIF has great potential for monitoring salmon meat freshness.

Study of Periodontal Bacteria in Diabetic Wistar Rats: Assessing the Anti-Inflammatory Effects of Carvacrol and Magnolol Hydrogels.

Periodontal disease and diabetes often co-occur; both are characterized by chronic inflammation. This study aimed to investigate the anti-inflammatory effects of carvacrol and magnolol when incorporated into a periodontal hydrogel and topically applied to Wistar rats with diabetes-associated periodontal disease. Forty male albino Wistar rats were divided into four groups: PD (induced diabetes and periodontitis), PDC (induced diabetes and periodontitis treated with carvacrol), PDM (induced diabetes and periodontitis treated with magnolol), and PDCM (induced diabetes and periodontitis treated with both carvacrol and magnolol). Post treatment, gingival tissue samples were collected to measure levels of the pro-inflammatory cytokines IL-6 and TNF-α. The PDCM group exhibited significantly lower levels of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) compared to the PD group. The combined application of a periodontal hydrogel containing carvacrol and magnolol may significantly reduce gingival inflammation in rats with diabetes-associated periodontal disease.

Experimental Insights on the Use of Secukinumab and Magnolol in Acute Respiratory Diseases in Mice.

This study investigates the combined treatment of secukinumab (SECU) and magnolol (MAGN) in a mouse model of LPS-induced ALI overlapped with allergic pulmonary inflammation, aiming to better understand the mechanism behind this pathology and to assess the therapeutic potential of this novel approach in addressing the severity of ALI. The combined treatment reveals intricate immunomodulatory effects. Both treatments inhibit IL-17 and promote M2 macrophage polarization, which enhances anti-inflammatory cytokine production such as IL-4, IL-5, IL-10, and IL-13, crucial for lung repair and inflammation resolution. However, the combination treatment exacerbates allergic responses and increases OVA-specific IgE, potentially worsening ALI outcomes. MAGN pretreatment alone demonstrates higher potency in reducing neutrophils and enhancing IFN-γ, suggesting its potential in mitigating severe asthma symptoms and modulating immune responses. The study highlights the need for careful consideration in therapeutic applications due to the combination treatment's inability to reduce IL-6 and its potential to exacerbate allergic inflammation. Elevated IL-6 levels correlate with worsened oxygenation and increased mortality in ALI patients, underscoring its critical role in disease severity. These findings offer valuable insights for the advancement of precision medicine within the realm of respiratory illnesses, emphasizing the importance of tailored therapeutic strategies.

A membrane-targeting magnolol derivative for the treatment of methicillin-resistant Staphylococcus aureus infections.

Multidrug-resistant bacterial infections are a major global health challenge, especially the emergence and rapid spread of methicillin-resistant Staphylococcus aureus (MRSA) urgently require alternative treatment options. Our study has identified that a magnolol derivative 6i as a promising agent with significant antibacterial activity against S. aureus and clinical MRSA isolates (MIC = 2-8 µg/mL), showing high membrane selectivity. Unlike traditional antibiotics, 6i demonstrated rapid bactericidal efficiency and a lower propensity for inducing bacterial resistance. Compound 6i also could inhibit biofilm formation and eradicate bacteria within biofilms. Mechanistic studies further revealed that 6i could target bacterial cell membranes, disrupting the integrity of the cell membrane and leading to increased DNA leakage, resulting in potent antibacterial effects. Meanwhile, 6i also showed good plasma stability and excellent biosafety. Notably, 6i displayed good in vivo antibacterial activity in a mouse skin abscess model of MRSA-16 infection, which was comparable to the positive control vancomycin. These findings indicated that the magnolol derivative 6i possessed the potential to be a novel anti-MRSA infection agent.

Novel composite fatty acid vesicles-in-Pluronic lecithin organogels for enhanced magnolol delivery in skin cancer treatment.

A novel composite carrier composed of Pluronic lecithin organogels and fatty acid vesicles was used to enhance the stability and facilitate the topical delivery of a natural bioactive drug, magnolol (Mag), for treatment of skin cancer. Jojoba oil was incorporated in the organogel (OG) base to provide a synergistic effect in treatment of skin cancer. The organoleptic properties, rheological behavior, morphology, and drug content of the OG formulations were investigated with emphasis on the impact of vesicle loading on the OG characteristics. The effect of OG on Mag release and ex-vivo permeation studies were evaluated and compared to free Mag in OG. The biological anti-tumor activity of the OG formulae was assessed using a skin cancer model in mice. All OG formulations exhibited uniform drug distribution with drug content ranging from 92.22 ± 0.91 to 100.45 ± 0.77 %. Rheological studies confirmed the OG shear-thinning flow behavior. Ex-vivo permeation studies demonstrated that the permeation of Mag from all OG formulations surpassed that obtained with free Mag in the OG. The anti-tumor activity studies revealed the superior efficacy of 10-hydroxy-decanoic acid (HDA)-based vesicles incorporated in OG formulations in mitigating 7,12- dimethylbenz(a)anthracene (DMBA)-induced skin cancer, thereby offering a promising platform for the local delivery of Mag.

Magnolol against enterovirus 71 by targeting Nrf2-SLC7A11-GSH pathway.

Enterovirus 71 (EV71), a prominent pathogen associated with hand, foot, and mouth disease (HFMD), has been reported worldwide. To date, the advancement of effective drugs targeting EV71 remains in the preliminary experimental stage. In this study, magnolol demonstrated a significant dose-dependent inhibition of EV71 replication in vitro. It upregulated the overall expression level of nuclear factor erythroid 2 - related factor 2 (Nrf2) and facilitated its nucleus translocation, resulting in the increased expression of various ferroptosis inhibitory genes. This process led to a reduction in reactive oxygen species (ROS) accumulation induced by viral infection. Additionally, magnolol exhibited a broad-spectrum antiviral effect against enteroviruses. Notably, treatment with magnolol substantially enhanced the survival rate of EV71-infected mice, attenuated viral load in heart, liver, brain, and limb tissues, and mitigated tissue inflammation. Taken together, magnolol emerges as a promising candidate for the development of anti-EV71 drugs.

Honokiol and magnolol: A review of structure-activity relationships of their derivatives.

Honokiol (HK) and magnolol (MAG) are typical representatives of neolignans possessing a wide range of biological activities and are employed as traditional medicines in Asia. In the past few decades, HK and MAG have been proven to be promising chemical scaffolds for the development of novel neolignan drugs. This review focuses on recent advances in the medicinal chemistry of HK and MAG derivatives, especially their structure-activity relationships. In addition, it also presents a comprehensive summary of the pharmacology, biosynthetic pathways, and metabolic characteristics of HK and MAG. This review can provide pharmaceutical chemists deeper insights into medicinal research on HK and MAG, and a reference for the rational design of HK and MAG derivatives.

Magnolol ameliorates fumonisin B1-induced oxidative damage and lipid metabolism dysfunction in astrocyte-like C6 cells.

The neurotoxicity of fumonisin B1 (FB1), a commonly detected mycotoxin in crops and the environment, has attracted considerable attention in recent years. However, no effective method for eliminating FB1 completely exists due to the thermal stability and water solubility of this mycotoxin. Magnolol (MAG) is a neolignane with antioxidative and neuroprotective effects. It has been applied in neurotoxicity treatment. However, the application of MAG to attenuate FB1-induced toxicity has not been reported. This study explored the protective mechanism of MAG against FB1-induced damage in C6 cells through antioxidant and lipid metabolism modulation. Results showed that exposure to 15 µM FB1 caused oxidative stress by changing the levels of malondialdehyde, reactive oxygen species, total superoxide dismutase, catalase, and total glutathione. These changes were reversed by MAG addition, especially at the concentration of 80 µM. The protective effects of MAG were further confirmed by the reduction in the phosphorylation levels of proteins in the MAPK signaling pathway. Lipidomics analysis identified 263 lipids, which belong to 24 lipid classes. Among all of the identified lipids, triglycerides (TGs), diglycerides (DGs), phosphatidylcholines (PCs), wax monoesters (WEs), Cers, and phosphatidylethanolamines (PEs) were major categories. Moreover, nine categories of lipids showed the opposite change trend in the FB1 exposure and MAG 80 groups. A further investigation of the 34 co-occurring differential lipids with remarkable changes (P value < 0.05 and VIP value > 1) in the control, FB1 exposure, and MAG 80 groups was performed. Therein, nine lipids (PCs, LPCs, and SM) were screened out as potential biomarkers to reveal the cytoprotective effects of MAG. This work is the first to investigate the rescue mechanism of MAG in FB1-induced cytotoxicity. The obtained results may expand the application of MAG to alleviate the toxicity of mycotoxins.

Extraction and Biological Activity of Lignanoids from Magnolia officinalis Rehder & E.H.Wilson Residual Waste Biomass Using Deep Eutectic Solvents.

Lignanoids are an active ingredient exerting powerful antioxidant and anti-inflammatory effects in the treatment of many diseases. In order to improve the efficiency of the resource utilization of traditional Chinese medicine waste, Magnolia officinalis Rehder & E.H.Wilson residue (MOR) waste biomass was used as raw material in this study, and a series of deep eutectic solvents (ChUre, ChAce, ChPro, ChCit, ChOxa, ChMal, ChLac, ChLev, ChGly and ChEG) were selected to evaluate the extraction efficiency of lignanoids from MORs. The results showed that the best conditions for lignanoid extraction were a liquid-solid ratio of 40.50 mL/g, an HBD-HBA ratio of 2.06, a water percentage of 29.3%, an extract temperature of 337.65 K, and a time of 107 min. Under these conditions, the maximum lignanoid amount was 39.18 mg/g. In addition, the kinetics of the extraction process were investigated by mathematic modeling. In our antioxidant activity study, high antioxidant activity of the lignanoid extract was shown in scavenging four different types of free radicals (DPPH, ·OH, ABTS, and superoxide anions). At a concentration of 3 mg/mL, the total antioxidant capacity of the lignanoid extract was 1.795 U/mL, which was equal to 0.12 mg/mL of Vc solution. Furthermore, the antibacterial activity study found that the lignanoid extract exhibited good antibacterial effects against six tested pathogens. Among them, Staphylococcus aureus exerted the strongest antibacterial activity. Eventually, the correlation of the lignanoid extract with the biological activity and physicochemical properties of DESs is described using a heatmap, along with the evaluation of the in vitro hypoglycemic, in vitro hypolipidemic, immunomodulatory, and anti-inflammatory activity of the lignanoid extract. These findings can provide a theoretical foundation for the extraction of high-value components from waste biomass by deep eutectic solvents, as well as highlighting its specific significance in natural product development and utilization.

Magnolol promotes the autophagy of esophageal carcinoma cells by upregulating HACE1 gene expression.

Esophagus cancer (EC) is one of the most aggressive malignant digestive system tumors and has a high clinical incidence worldwide. Magnolol, a natural compound, has anticancer effects on many cancers, including esophageal carcinoma, but the underlying mechanism has not been fully elucidated. Here, we first find that magnolol inhibits the proliferation of esophageal carcinoma cells and enhances their autophagy activity in a dose- and time-dependent manner. This study demonstrates that magnolol increases the protein levels of LC3 II, accompanied by increased HACE1 protein levels in both esophageal carcinoma cells and xenograft tumors. HACE1-knockout (KO) cell lines are generated, and the ablation of HACE1 eliminates the anti-proliferative and autophagy-inducing effects of magnolol on esophageal carcinoma cells. Additionally, our results show that magnolol primarily promotes HACE1 expression at the transcriptional level. Therefore, this study shows that magnolol primarily exerts its antitumor effect by activating HACE1-OPTN axis-mediated autophagy. It can be considered a promising therapeutic drug for esophageal carcinoma.

Improving cellular uptake and synergetic anti-tumor effects of magnolol and Brucea javanica oil through self-microemulsion.

OBJECTIVE: Magnolol (MG) and Brucea javanica (L.) Merr. oil (BJO) possess synergetic anti-tumor effects, but have poor water solubility and stability, which results in low oral bioavailability. SIGNIFICANCE: The MG loaded self-microemulsion drug delivery system (MG-SMDDS) with BJO as oil phase component was utilized to improve the cellular uptake and synergetic anti-tumor effects. METHODS: Compatibility study and pseudoternary phase diagram (PTPD) were respectively employed to screen for the composition and proportion of oil phase in the formulation. Central composite design-effect surface method was applied to optimize proportion of each formulation condition. The droplet size, ζ-potential, colloid stability, encapsulation rate (ER) and in vitro dissolution rate of MG-SMDDS were evaluated. Furthermore, cellular uptake and cytotoxicity of the microemulsion on HepG2 cells were assessed. RESULTS: The optimal composition of MG-SMDDS was: MG (9.09%), castor oil (7.40%), BJO (2.47%), Cremophor EL 35 (54.04%) and 1, 2-propanediol (27.01%). The MG-SMDDS exhibited satisfactory droplet size, ζ-potential, colloid stability and ER, as well as faster dissolution rate than free MG. More importantly, SMEDDS containing BJO could enhance the cellular uptake and cytotoxicity of free BJO and free MG on tumor cells. CONCLUSIONS: The BJO self-microemulsion delivery technique can provide an idea for design of oral delivery vehicles based on BJO.

Magnolol derivatives as specific and noncytotoxic inhibitors of breast cancer resistance protein (BCRP/ABCG2).

The breast cancer resistance protein (BCRP/ABCG2) transporter mediates the efflux of numerous antineoplastic drugs, playing a central role in multidrug resistance related to cancer. The absence of successful clinical trials using specific ABCG2 inhibitors reveals the urge to identify new compounds to attend this critical demand. In this work, a series of 13 magnolol derivatives was tested as ABCG2 inhibitors. Only two compounds, derivatives 10 and 11, showed partial and complete ABCG2 inhibitory effect, respectively. This inhibition was selective toward ABCG2, since none of the 13 compounds inhibited neither P-glycoprotein nor MRP1. Both inhibitors (10 and 11) were not transported by ABCG2 and demonstrated a low cytotoxic profile even at high concentrations (up to 100 µM). 11 emerged as the most promising compound of the series, considering the ratio between cytotoxicity (IG50) and ABCG2 inhibition potency (IC50), showing a therapeutic ratio (TR) higher than observed for 10 (10.5 versus 1.6, respectively). This derivative showed a substrate-independent and a mixed type of inhibition. The effect of compound 11 on the ABCG2 ATPase activity and thermostability revealed allosteric protein changes. This compound did not affect the expression levels of ABCG2 and increased the binding of the conformational-sensitive antibody 5D3. A docking study showed that 11 did not share the same binding site with ABCG2 substrate mitoxantrone. Finally, 11 could revert the chemoresistance to SN-38 mediated by ABCG2.

Construction of Magnolol Nanoparticles for Alleviation of Ethanol-Induced Acute Gastric Injury.

Ethanol (EtOH) has been identified as a potential pathogenic factor in gastric ulcer development primarily due to its association with gastric injury and excessive production of reactive oxygen species. Magnolol (Mag), the principal active compound in Magnolia officinalis extract, is well studied for its notable anti-inflammatory and antioxidant properties. However, its limited solubility, propensity for agglomeration, and low absorption and utilization rates significantly restrict its therapeutic use. This study aims to overcome these challenges by developing a Mag nanoparticle system targeting the treatment and prevention of EtOH-induced gastric ulcers in mice. Utilizing a click chemistry approach, we successfully synthesized this system by reacting thiolated bovine serum albumin (BSA·SH) with Mag. The in vitro analysis revealed effective uptake of the BSA·SH-Mag nanoparticle system by human gastric epithelial cells (GES-1), showcasing its antioxidant and anti-inflammatory capabilities. Additionally, BSA·SH-Mag exhibited gradual disintegration and release in simulated gastric fluid, resulting in a notable reduction of oxidative stress in gastric tissues and mucosal tissue repair and effectively reducing inflammatory expression. Furthermore, BSA·SH-Mag attenuated EtOH-induced gastric inflammation by decreasing the level of NOX4 protein expression and augmenting the level of Nrf2 protein expression. In conclusion, our findings indicate that BSA·SH-Mag represents a promising candidate as an oral therapeutic for gastric ulcer treatment.

Magnolol Reduces Atopic Dermatitis-like Symptoms in BALB/c Mice.

In traditional Korean medicines, Magnolia officinalis is commonly included for the remedy of atopic dermatitis, and magnolol is a major constituent of Magnolia officinalis. Its pharmacological effects include anti-inflammatory, hepatoprotective, and antioxidant effects. Using BALB/c mice repeatedly exposed to 1-chloro-2,4-dinitrobenzene (DNCB), magnolol was evaluated in atopic dermatitis-like lesions. Administration of magnolol (10 mg/kg, intraperitoneal injection) markedly relieved the skin lesion severity including cracking, edema, erythema, and excoriation, and significantly inhibited the increase in IgE levels in the peripheral blood. A DNCB-induced increase in mast cell accumulation in atopic dermatitis skin lesions was reversed by magnolol administration, as well as a rise in expression levels of pro-inflammatory Th2/Th17/Th1 cytokines' (IL-4, IL-13, IL-17A, IFN-γ, IL-12A, TARC, IL-8, and IL-6) mRNAs in the lymph nodes and skin (n = 5 per group). In lymph nodes, magnolol reversed DNCB's increase in CD4+RORγt+ Th17 cell fraction and decrease in CD4+FoxP3+ regulatory T cell fraction. The results also showed that magnolol suppressed T cell differentiation into Th17 and Th2 cells, but not Th1 cells. Magnolol suppresses atopic dermatitis-like responses in the lymph nodes and skin, suggesting that it may be feasible to use it as a treatment for atopic dermatitis through its suppression of Th2/Th17 differentiation.

Sirtuin 1 in osteoarthritis: Perspectives on regulating glucose metabolism.

Osteoarthritis (OA) is a degenerative disease characterised by articular cartilage destruction, and its complex aetiology contributes to suboptimal clinical treatment outcomes. A close association exists between glucose metabolism dysregulation and OA pathogenesis. Owing to the unique environment of low oxygen and glucose concentrations, chondrocytes rely heavily on their glycolytic capacity, exhibiting distinct spatiotemporal differences. However, under pathological stimulation, chondrocytes undergo excessive glycolytic activity while mitochondrial respiration and other branches of glucose metabolism are compromised. This metabolic change induces cartilage degeneration by reprogramming the inflammatory responses. Sirtuins, a highly conserved family of nicotinamide adenine dinucleotide (NAD+)-dependent deacetylases, regulate glucose metabolism in response to energy fluctuations in different cellular compartments，alleviating metabolic stress. SIRT1, the most extensively studied sirtuin, participates in maintaining glucose homeostasis in almost all key metabolic tissues. While actively contributing to the OA progression and displaying diverse biological effects in cartilage protection, SIRT1's role in regulating glucose metabolism in chondrocytes has not received sufficient attention. This review focuses on discussing the beneficial role of SIRT1 in OA progression from a metabolic regulation perspective based on elucidating the primary characteristics of chondrocyte glucose metabolism. We also summarise the potential mechanisms and therapeutic strategies targeting SIRT1 in chondrocytes to guide clinical practice and explore novel therapeutic directions.

Magnolol attenuates macrophage pyroptosis triggered by Streptococcus equi subsp. zooepidemicus.

Streptococcus equi subsp. zooepidemicus (SEZ) is a zoonotic bacterial pathogen that causes life-threatening infections and various diseases such as meningitis, endocarditis and pneumonia. With the use of antibiotics being severely restricted in the international community, an alternative to antibiotics is urgently needed against bacterial. In the present study, the herbal extract magnolol protected mice against SEZ infection, reflected by increased survival rate and reduced bacterial burden. A pro-inflammatory form of cell death occurred in SEZ-infected macrophage. Magnolol downregulated the expression of pyroptosis-related proteins and reduced the formation of cell membrane pores in infected macrophages to suppress the development of subsequent inflammation. We further demonstrated that magnolol directly suppressed SEZ-induced macrophage pyroptosis, which partially protected macrophages from SEZ infection. Our study revealed that magnolol suppressed inflammation and protected mice against SEZ infection, providing a possible treatment for SEZ infection.

Hyaluronic acid-functionalized DDAB/PLGA nanoparticles for improved oral delivery of magnolol in the treatment of ulcerative colitis.

Dysfunction of the mucosal barrier as well as local inflammation are major challenges in the treatment of ulcerative colitis (UC). Mag, a natural compound derived from traditional Chinese medicine, has been shown to have anti-inflammatory and mucosal protection properties. However, its poor gastrointestinal stability as well as its insufficient accumulation in inflamed colonic lesions limit its potential use as an alternative therapeutic drug in UC. The present research involved the design and preparation of a hybrid nanoparticle system (LPNs) specifically targeting macrophages at the colonic site. This was achieved by electrostatically adsorbing HA onto positively charged lipid-polymer hybrid nanoparticles (HA-LPNs). The prepared HA-LPNs exhibited a rounded morphology and a narrow size distribution. In vitro, the anti-inflammatory efficacy of Mag-HA-LPNs (which control levels of the pro-inflammatory cytokines NO, IL-6 and TNF-α) was assessed in RAW 264.7 cells. Analysis by flow cytometry and fluorescence microscopy demonstrated increased cellular uptake through HA/CD44 interaction. As expected, Mag-HA-LPNs was found to effectively increased colon length and reduced DAI scores in DSS-treated mice. This effect was achieved by regulating the inflammatory cytokines level and promoting the restoration of the colonic mucosal barrier through increased expression of Claudin-1, ZO-1 and Occludin. In this study, we developed an efficient and user-friendly delivery method for the preparation of HA-functionalized PLGA nanoparticles, which are intended for oral delivery of Mag. The findings suggest that these HA-LPNs possess the potential to serve as a promising approach for direct drug delivery to the colon for effective treatment of UC.

Magnolol and 5-fluorouracil synergy inhibition of metastasis of cervical cancer cells by targeting PI3K/AKT/mTOR and EMT pathways.

Objective: This study is designed to investigate the mode of action of the synergistic effect of 5-fluorouracil (5-FU) and magnolol against cervical cancer. Methods: Network pharmacological approach was applied to predict the molecular mechanism of 5-FU combined with magnolol against cervical cancer. CCK-8 assay, colony formation assay, immunofluorescence staining, adhesion assay, wound healing mobility assay, cell migration and invasion assay and Western blot analysis were conducted to validate the results of in silico study. Results: Phosphatidylinositol 3 kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling pathway was identified as the key pathway in silico study. The experimental results showed that 5-FU combined with magnolol strongly inhibited cervical cancer cell proliferation, induced the morphological change of HeLa cells by down-regulating the expression of α-actinin, tensin-2 and vinculin. Moreover, magnolol enhanced inhibitory effect of 5-FU on the cell adhesion, migration and invasion. The phosphorylation of AKT and PI3K and the expression of mTOR were strongly inhibited by the combination of 5-FU and magnolol. Moreover, the expression of E-cadherin and ß-catenin was upregulated and the expression of Snail, Slug and vimentin was down-regulated by the 5-FU together with magnolol. Conclusion: Taken together, this study suggests that 5-FU combined with magnolol exerts a synergistic anti-cervical cancer effect by regulating the PI3K/AKT/mTOR and epithelial-mesenchymal transition (EMT) signaling pathways.

The natural compounds, Magnolol or Honokiol, promote adipose tissue browning and resist obesity through modulating PPARα/γ activity.

Non-alcoholic fatty liver disease (NAFLD) is closely associated with the body's energy metabolism. A potential strategy to regulate energy metabolism, combat obesity, and reduce NAFLD is by enhancing adipocyte thermogenesis and increasing energy expenditure. In this study, our objective was to examine the effects of phenolic extracts derived from Magnolia officinalis on the regulation of NAFLD. Specifically, we investigated the impact of Magnolol or Honokiol treatment on high-fat diet (HFD)-induced obese C57BL6/J male mice. Firstly, we monitored energy metabolism, dissected tissues, and analyzed tissue sections. Additionally, we conducted experiments on HepG2 and primary adipocytes to gain insights into the roles of Magnolol or Honokiol. To further understand the effects of these compounds on related signaling pathways and marker genes, we performed molecular docking, dual-luciferase assays, and interfered with target genes. Our findings revealed that Magnolol or Honokiol activate the peroxisome proliferator activated receptor alpha (PPARα) signaling pathway, leading to the alleviation of NAFLD. This activation promotes fatty acid oxidation, reduces lipogenesis, and enhances the expression and secretion of FGF21. Notably, Fibroblast growth factor 21 (FGF21), secreted by the liver, plays a crucial role in improving communication between the liver and adipocytes while also promoting the browning of adipose tissue. Additionally, Magnolol or Honokiol activate the peroxisome proliferator activated receptor gamma (PPARγ) signaling pathway, resulting in increased uncoupling protein 1 (UCP1) expression, heightened heat production in adipose tissue, and anti-obesity. Therefore, Magnolol or Honokiol alleviate NAFLD, promote adipose tissue browning and resist obesity through dual activation of PPARα/γ.

Identification and Validation of Magnolol Biosynthesis Genes in Magnolia officinalis.

Bacterial infections pose a significant risk to human health. Magnolol, derived from Magnolia officinalis, exhibits potent antibacterial properties. Synthetic biology offers a promising approach to manufacture such natural compounds. However, the plant-based biosynthesis of magnolol remains obscure, and the lack of identification of critical genes hampers its synthetic production. In this study, we have proposed a one-step conversion of magnolol from chavicol using laccase. After leveraging 20 transcriptomes from diverse parts of M. officinalis, transcripts were assembled, enriching genome annotation. Upon integrating this dataset with current genomic information, we could identify 30 laccase enzymes. From two potential gene clusters associated with magnolol production, highly expressed genes were subjected to functional analysis. In vitro experiments confirmed MoLAC14 as a pivotal enzyme in magnolol synthesis. Improvements in the thermal stability of MoLAC14 were achieved through selective mutations, where E345P, G377P, H347F, E346C, and E346F notably enhanced stability. By conducting alanine scanning, the essential residues in MoLAC14 were identified, and the L532A mutation further boosted magnolol production to an unprecedented level of 148.83 mg/L. Our findings not only elucidated the key enzymes for chavicol to magnolol conversion, but also laid the groundwork for synthetic biology-driven magnolol production, thereby providing valuable insights into M. officinalis biology and comparative plant science.