Aloe Emodin Reduces Cardiac Inflammation Induced by a High-Fat Diet through the TLR4 Signaling Pathway

Modulation of atherosclerosis-related signaling pathways by Chinese herbal extracts: Recent evidence and perspectives

Atherosclerotic cardiovascular disease remains a preeminent cause of morbidity and mortality globally. The onset of atherosclerosis underpins the emergence of ischemic cardiovascular diseases, including coronary heart disease (CHD). Its pathogenesis entails multiple factors such as inflammation, oxidative stress, apoptosis, vascular endothelial damage, foam cell formation, and platelet activation. Furthermore, it triggers the activation of diverse signaling pathways including Phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt), NF-E2-related factor 2/antioxidant response element (Nrf2/ARE), the Notch signaling pathway, peroxisome proliferator-activated receptor (PPAR), nucleotide oligo-structural domain-like receptor thermoprotein structural domain-associated protein 3 (NLRP3), silencing information regulator 2-associated enzyme 1 (Sirt1), nuclear transcription factor-κB (NF-κB), Circular RNA (Circ RNA), MicroRNA (mi RNA), Transforming growth factor-β (TGF-β), and Janus kinase-signal transducer and activator of transcription (JAK/STAT). Over recent decades, therapeutic approaches for atherosclerosis have been dominated by the utilization of high-intensity statins to reduce lipid levels, despite significant adverse effects. Consequently, there is a growing interest in the development of safer and more efficacious drugs and therapeutic modalities. Traditional Chinese medicine (TCM) offers a vital strategy for the prevention and treatment of cardiovascular diseases. Numerous studies have detailed the mechanisms through which TCM active ingredients modulate signaling molecules and influence the atherosclerotic process. This article reviews the signaling pathways implicated in the pathogenesis of atherosclerosis and the advancements in research on TCM extracts for prevention and treatment, drawing on original articles from various databases including Google Scholar, Medline, CNKI, Scopus, and Pubmed. The objective is to furnish a reference for the clinical management of cardiovascular diseases.

New opportunities and perspectives on biosynthesis and bioactivities of secondary metabolites from Aloe vera

Historically, the genus Aloe has been an indispensable part of both traditional and modern medicine. Decades of intensive research have unveiled the major bioactive secondary metabolites of this plant. Recent pandemic outbreaks have revitalized curiosity in aloe metabolites, as they have proven pharmacokinetic profiles and repurposable chemical space. However, the structural complexity of these metabolites has hindered scientific advances in the chemical synthesis of these compounds. Multi-omics research interventions have transformed aloe research by providing insights into the biosynthesis of many of these compounds, for example, aloesone, aloenin, noreugenin, aloin, saponins, and carotenoids. Here, we summarize the biological activities of major aloe secondary metabolites with a focus on their mechanism of action. We also highlight the recent advances in decoding the aloe metabolite biosynthetic pathways and enzymatic machinery linked with these pathways. Proof-of-concept studies on in vitro, whole-cell, and microbial synthesis of aloe compounds have also been briefed. Research initiatives on the structural modification of various aloe metabolites to expand their chemical space and activity are detailed. Further, the technological limitations, patent status, and prospects of aloe secondary metabolites in biomedicine have been discussed.

Aloe-emodin from Sanhua Decoction inhibits neuroinflammation by regulating microglia polarization after subarachnoid hemorrhage

ETHNOPHARMACOLOGICAL RELEVANCE

Subarachnoid hemorrhage (SAH) triggers a cascade of events that lead to early brain injury (EBI), which contributes to poor outcomes and appears within 3 days after SAH initiation. EBI involves multiple process including neuronal death, blood-brain barrier (BBB) injury and inflammation response. Microglia are cluster of immune cells originating in the brain which respond to SAH by changing their states and releasing inflammatory molecules through various signaling pathways. M0, M1, M2 are three states of microglia represent resting state, promoting inflammation state, and anti-inflammation state respectively, which can be modulated by pharmacological strategies.

AIM OF THE STUDY

After identified potential active ingredients and targets of Sanhua Decoction (SHD) for SAH, we selected aloe-emodin (AE) as a potential ingredient modulating microglia activation states.

MATERIALS AND METHODS

Molecular mechanisms, targets and pathways of SHD were reveal by network pharmacology technique. The effects of AE on SAH were evaluated in vivo by assessing neurological deficits, neuronal apoptosis and BBB integrity in a mouse SAH model. Furthermore, BV-2 cells were used to examine the effects of AE on microglial polarization. The influence of AE on microglia transformation was measured by Iba-1, TNF-α, CD68, Arg-1 and CD206 staining. The signal pathways of neuronal apoptosis and microglia polarization was measured by Western blot.

RESULTS

Network pharmacology identified potential active ingredients and targets of SHD for SAH. And AE is one of the active ingredients. We also confirmed that AE via NF-κB and PKA/CREB pathway inhibited the microglia activation and promoted transformation from M1 phenotype to M2 at EBI stage after SAH.

CONCLUSIONS

AE, as one ingredient of SHD, can alleviate the inflammatory response and protecting neurons from SAH-induced injury. AE has potential value for treating SAH-induced nerve injury and is expected to be applied in clinical practice.

Anthraquinones against Cryptococcus neoformans sensu stricto: antifungal interaction, biofilm inhibition and pathogenicity in the Caenorhabditis elegans model

Introduction. Cryptococcal biofilms have been associated with persistent infections and antifungal resistance. Therefore, strategies, such as the association of natural compounds and antifungal drugs, have been applied for the prevention of biofilm growth. Moreover, the Caenorhabditis elegans pathogenicity model has been used to investigate the capacity to inhibit the pathogenicity of Cryptococcus neoformans sensu stricto.Hypothesis. Anthraquinones and antifungals are associated with preventing C. neoformans sensu stricto biofilm formation and disrupting these communities. Antraquinones reduced the C. neoformans sensu stricto pathogenicity in the C. elegans model.Aim. This study aimed to evaluate the in vitro interaction between aloe emodin, barbaloin or chrysophanol and itraconazole or amphotericin B against growing and mature biofilms of C. neoformans sensu stricto.Methodology. Compounds and antifungal drugs were added during biofilm formation or after 72 h of growth. Then, the metabolic activity was evaluated by the MTT reduction assay, the biomass by crystal-violet staining and the biofilm morphology by confocal laser scanning microscopy. C. neoformans sensu stricto's pathogenicity was investigated using the nematode C. elegans. Finally, pathogenicity inhibition by aloe emodin, barbarloin and chrysophanol was investigated using this model.Results. Anthraquinone-antifungal combinations affected the development of biofilms with a reduction of over 60 % in metabolic activity and above 50 % in biomass. Aloe emodin and barbaloin increased the anti-biofilm activity of antifungal drugs. Chrysophanol potentiated the effect of itraconazole against C. neoformans sensu stricto biofilms. The C. elegans mortality rate reached 76.7 % after the worms were exposed to C. neoformans sensu stricto for 96 h. Aloe emodin, barbaloin and chrysophanol reduced the C. elegans pathogenicity with mortality rates of 61.12 %, 65 % and 53.34 %, respectively, after the worms were exposed for 96 h to C. neoformans sensu stricto and these compounds at same time.Conclusion. These results highlight the potential activity of anthraquinones to increase the effectiveness of antifungal drugs against cryptococcal biofilms.

Formulation, characterization and and evaluation of aloe-emodin-loaded solid dispersions for dissolution enhancement

OBJECTIVE

To prepare aloe-emodin solid dispersion (AE-SD) and determine the metabolic process of AE and AE-SD in vivo.

METHODS

AE-SD was prepared viasolvent evaporation or solvent melting using PEG-6000 and PVP-K30 as carriers. Thermogravimetric analysis, X-ray diffraction spectroscopy, differential scanning calorimetry, Fourier transform infrared spectroscopy and scanning electron microscopy were used to identify the physical state of AE-SD. Optimal prescriptions were screened viathe dissolution degree determination method. Using Phoenix software, AE suspension and AE-SD were subjected to a pharmacokinetic comparison study analyzing the alteration of behavior in vivo after AE was prepared as a solid dispersion. Acute toxicity was assessed in mice, and the physiological toxicity was used as the determination criterion for toxicity.

RESULTS

AE-SD showed that AE existed in the carrier in an amorphous state. Compared with polyethylene glycol, polyvinylpyrrolidone (PVP) inhibited AE crystallization, causing the drug to transform from a dense crystalline state to an amorphous form and increasing the degree of drug dispersion. Therefore, it was more suitable as a carrier material for AE-SD. The addition of poloxamer (POL) was more beneficial to the stability of solid dispersions and could reduce the amount of PVP. The dissolution test confirmed that the optimal ratio of AE to the composite vector AE-PVP-POL was 1：2：2, and its dissolution effect was also optimal. Based on the pharmacokinetic comparison, the drug absorption was faster and quickly reached the peak of blood drug concentration in AE-SD compared to AE, the Cmax of AE-SD was greater than that of AE, and t1/2 and mean residence time of AE-SD were less than AE. The results showed that the drug metabolism in AE-SD was better, and the residence time was shorter. The toxicology study showed that both AE and AE-SD had no toxicity.

CONCLUSION

This paper established that the solubility of the drug could be increased after preparing a solid dispersion, as demonstrated by in vitro dissolution experiments. In vivo pharmacokinetics studies confirmed that AE-SD could improve the bioavailability of AE in vivo, providing a new concept for the research and development of AE preparations.

Aloe-Emodin Isolated from Rheum Undulatum L. Regulates Cell Cycle Distribution and Cellular Senescence in Human Prostate Cancer LNCaP Cells

Senescence can promote hyperplastic pathologies, such as cancer. Prostate cancer is the second most common type of cancer in men. The p21-mediate cellular senescence, facilitated through the tumor suppressor p53-dependent pathway, is considered the primary mechanism for cancer treatment. Aloe-emodin, has been reported to exert anticancer effects in various types of cancers. This study aimed to investigate the bioactivity of aloe-emodin in LNCaP cells via the activation of p21-mediated cellular senescence. Aloe-emodin treatment increased the percentage of cells in the G1 phase while decreasing the percentage in the S phase. This effect was reflected in the expression levels of proteins associated with cell cycle progression, such as p21CIP, retinoblastoma protein, and cyclin-dependent kinase2/4 in LNCaP cells. However, aloe-emodin-treated LNCaP cells did not induce cell cycle arrest at G2/M checkpoint. Moreover, increased senescence-associated-galactosidase activity was observed in a dose-dependent manner following treatment with aloe-emodin. Aloe-emodin also induced DNA damage by modulating the expression of histone H2AX and lamin B1. Furthermore, aloe-emodin inhibited the proliferation of LNCaP cells, contrasting with the exponential growth observed in the nontreated cells. Importantly, this inhibition did not impact the immune system, as evidenced by the increased proliferation of splenocytes isolated from mice. These findings provide preliminary evidence of the anticancer effect of aloe-emodin in LNCaP cells, necessitating further investigations into the underlying mechanisms in vivo and human subjects.

Emodin exhibits anti-acne potential by inhibiting cell growth, lipogenesis, and inflammation in human SZ95 sebocytes

Emodin, a natural anthraquinone derivative, possesses anti-proliferative and anti-inflammatory properties in skin diseases. However, little information is available on the efficacy of emodin in treating acne vulgaris (acne). This study aims to investigate the protective effects and potential mechanisms of emodin as an anti-acne agent. In vitro, SZ95 sebocytes was chose to establish an acneigenic cellular model. We found that emodin effectively inhibited proliferation, induced cell cycle arrest and apoptosis of SZ95 sebocytes in a dose-dependent manner. To evaluate the lipid-lowering potential of emodin, we examined the levels of lipid contents and lipogenic transcription factors, and found that both lipid production and protein expression of PPARγ, LXR α/β, and SREBP-1 were decreased after treatment with emodin. Furthermore, our results revealed that emodin inhibited sebaceous lipogenesis induced by insulin-like growth factor 1 (IGF-1), which was accompanied by a potent inhibition of the phosphoinositide-3-kinase (PI3K)/Akt/forkhead box protein O1 (FoxO1) pathway. In detail, emodin augmented the inhibitory effect of isotretinoin and PI3K inhibitor LY294002, while attenuating the activation of IGF-1 on PI3K/Akt/FoxO1 pathway. In addition, emodin could decrease the secretion of pro-inflammatory cytokines IL-6 and IL-8, and suppress the expression of NLRP3, capase-1, IL-1β, and IL-18 in SZ95 sebocytes exposed to Cutibacterium acnes. Overall, our study provides preliminary evidence supporting the anti-growth, anti-lipogenic and anti-inflammatory properties of emodin, indicating the potential therapeutic application of emodin for acne treatment.

Active ingredients of Erhuang Quzhi Granules for treating non-alcoholic fatty liver disease based on the NF-κB/NLRP3 pathway

Erhuang Quzhi Granules (EQG), the Chinese herbal compound, has demonstrated significant clinical efficacy in treating non-alcoholic fatty liver disease (NAFLD). The mechanism of this treatment has been shown to involve the nuclear factor kappa B (NF-κB)/nod-like receptor thermal protein domain associated protein 3 (NLRP3) pathway. However, research on the material basis of EQG against NAFLD is still in its primary stages. Following these considerations, this study predicted and screened the active ingredients of EQG using the absorption, distribution, metabolism, and excretion (ADME) property evaluation tool and molecular docking. Then the levels of these active ingredients in EQG were measured using ultra-high-performance liquid chromatography (UHPLC). The efficacy of the active ingredients and their mechanisms were validated through both in vivo and in vitro experiments. The results indicate that the collected 12 components have favorable metabolic stability, are safe, and have drug-like properties. Aloe-emodin (AE), rhein (RH), curcumin (CUR), emodin (EM), and chrysophanol (CP) showed better binding affinity with TNF-α and Caspase-1 proteins. UHPLC analysis revealed that EQG contains AE, RH, CUR, EM, and CP. Cellular experiments proved that all these five ingredients reduce the accumulation of lipids and reactive oxygen species. In animal models of NAFLD, AE, and RH significantly improved the pathological symptoms of steatosis and fibrosis and reduced the levels of pro-inflammatory factors via the NF-κB/NLRP3 pathway. The results reveal the active ingredients of EQG for treating NAFLD based on the NF-κB/NLRP3 pathway and lay the foundation for the clinical promotion of EQG.

Aloe-Emodin Derivative, an Anthraquinone Compound, Attenuates Pyroptosis by Targeting NLRP3 Inflammasome in Diabetic Cardiomyopathy

Diabetic cardiomyopathy (DCM) is widely recognized as a major contributing factor to the development of heart failure in patients with diabetes. Previous studies have demonstrated the potential benefits of traditional herbal medicine for alleviating the symptoms of cardiomyopathy. We have chemically designed and synthesized a novel compound called aloe-emodin derivative (AED), which belongs to the aloe-emodin (AE) family of compounds. AED was formed by covalent binding of monomethyl succinate to the anthraquinone mother nucleus of AE using chemical synthesis techniques. The purpose of this study was to investigate the effects and mechanisms of AED in treating DCM. We induced type 2 diabetes in Sprague-Dawley (SD) rats by administering a high-fat diet and streptozotocin (STZ) injections. The rats were randomly divided into six groups: control, DCM, AED low concentration (50 mg/kg/day), AED high concentration (100 mg/kg/day), AE (100 mg/kg/day), and positive control (glyburide, 2 mg/kg/day) groups. There were eight rats in each group. The rats that attained fasting blood glucose of ˃16.7 mmol/L were considered successful models. We observed significant improvements in cardiac function in the DCM rats with both AED and AE following four weeks of intragastric treatment. However, AED had a more pronounced therapeutic effect on DCM compared to AE. AED exhibited an inhibitory effect on the inflammatory response in the hearts of DCM rats and high-glucose-treated H9C2 cells by suppressing the pyroptosis pathway mediated by the nucleotide-binding oligomerization domain (NOD)-like receptor pyrin domain 3 (NLRP3) inflammasome. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of differentially expressed genes showed a significant enrichment in the NOD-like receptor signaling pathway compared to the high-glucose group. Furthermore, overexpression of NLRP3 effectively reversed the anti-pyroptosis effects of AED in high-glucose-treated H9C2 cells. This study is the first to demonstrate that AED possesses the ability to inhibit myocardial pyroptosis in DCM. Targeting the pyroptosis pathway mediated by the NLRP3 inflammasome could provide a promising therapeutic strategy to enhance our understanding and treatment of DCM.

Aloe-emodin ameliorated MI-induced cardiac remodeling in mice via inhibiting TGF-β/SMAD signaling via up-regulating SMAD7

BACKGROUND

Aloe-emodin (AE), a natural anthraquinone extract from traditional Chinese medicinal plants, has been certified to protect against acute myocardial ischemia. However, its effect on cardiac remodeling after chronic myocardial infarction (MI) and the possible mechanism remain unclear.

PURPOSE

This study investigated the effect of AE on cardiac remodeling and oxidative damage induced by myocardial infarction (MI) in vitro and explored the underlying mechanisms.

METHODS

Echocardiography and Masson staining were used to demonstrate myocardial dysfunction and fibrosis. Cell apoptosis was detected by TUNEL staining. The expressions of fibrosis-related factors such as type I collagen, α-smooth muscle actin (α-SMA) and connective tissue growth factor (CTGF) were detected by Western blot.

RESULTS

Our data demonstrated that AE treatment significantly improved cardiac function, reduced structural remodeling, and reduced cardiac apoptosis and oxidative stress in mice with myocardial infarction. In vitro, AE could protect neonatal mouse cardiomyocytes (NMCM) from angiotensin II (Ang II)-induced cardiomyocyte hypertrophy and apoptosis, and significantly inhibited (p < 0.05) Ang II-induced reactive oxygen species (ROS) increase. Furthermore, AE treatment significantly reversed the Ang ii-induced upregulation.

CONCLUSION

In summary, our work reveals for the first time that AE activates the TGF-β signaling pathway by up-regulating Smad7 expression, which in turn regulates the expression of fibrosis-related genes, ultimately improving cardiac function, inhibiting the development of cardiac fibrosis and hypertrophy in rats with chronic MI.

Jinyinqingre Oral Liquid alleviates LPS-induced acute lung injury by inhibiting the NF-κB/NLRP3/GSDMD pathway

Acute lung injury (ALI) is a prevalent and severe clinical condition characterized by inflammatory damage to the lung endothelial and epithelial barriers, resulting in high incidence and mortality rates. Currently, there is a lack of safe and effective drugs for the treatment of ALI. In a previous clinical study, we observed that Jinyinqingre oral liquid (JYQR), a Traditional Chinese Medicine formulation prepared by the Taihe Hospital, Affiliated Hospital of Hubei University of Medicine, exhibited notable efficacy in treating inflammation-related hepatitis and cholecystitis in clinical settings. However, the potential role of JYQR in ALI/acute respiratory distress syndrome (ARDS) and its anti-inflammatory mechanism remains unexplored. Thus, the present study aimed to investigate the therapeutic effects and underlying molecular mechanisms of JYQR in ALI using a mouse model of lipopolysaccharide (LPS)-induced ALI and an in vitro RAW264.7 cell model. JYQR yielded substantial improvements in LPS-induced histological alterations in lung tissues. Additionally, JYQR administration led to a noteworthy reduction in total protein levels within the BALF, a decrease in MPAP, and attenuation of pleural thickness. These findings collectively highlight the remarkable efficacy of JYQR in mitigating the deleterious effects of LPS-induced ALI. Mechanistic investigations revealed that JYQR pretreatment significantly inhibited NF-κB activation and downregulated the expressions of the downstream proteins, namely NLRP3 and GSDMD, as well as proinflammatory cytokine levels in mice and RAW2647 cells. Consequently, JYQR alleviated LPS-induced ALI by inhibiting the NF-κB/NLRP3/GSDMD pathway. JYQR exerts a protective effect against LPS-induced ALI in mice, and its mechanism of action involves the downregulation of the NF-κB/NLRP3/GSDMD inflammatory pathway.

Multiple Beneficial Effects of Aloesone from Aloe vera on LPS-Induced RAW264.7 Cells, Including the Inhibition of Oxidative Stress, Inflammation, M1 Polarization, and Apoptosis

Aloesone is a major metabolic compound in Aloe vera, which has been widely used as a food source and therapeutic agent in several countries. Our recent study demonstrated that aloesone has anti-epileptic effects on glutamate-induced neuronal injury by suppressing the production of reactive oxygen species (ROS). Unless ROS are naturally neutralized by the endogenous antioxidant system, they lead to the activation of inflammation, polarization, and apoptosis. This study aimed to identify the multiple beneficial effects of aloesone and explore its molecular mechanism in macrophages. Hence, the murine macrophage cell line RAW264.7 was pretreated with aloesone and then exposed to lipopolysaccharides (LPS). The results demonstrated that aloesone, within a dosage range of 0.1-100 µM, dramatically decreased the LPS-induced elevation of ROS production, reduced nitric oxide (NO) release, inhibited the M1 polarization of RAW264.7 cells, and prevented cells from entering the LPS-induced early and late phases of apoptosis in a dose-dependent manner. Simultaneously, aloesone significantly decreased the mRNA expression of inflammation-related genes (iNOS, IL-1ꞵ, TNF-α) and increased the expression of antioxidant enzymes (Gpx-1 and SOD-1). The core genes HSP90AA1, Stat3, Mapk1, mTOR, Fyn, Ptk2b, and Lck were closely related to these beneficial effects of aloesone. Furthermore, immunofluorescence staining and flow cytometry data confirmed that aloesone significantly repressed the activation of mTOR, p-mTOR, and HIF-1α induced by LPS and inhibited the protein expression of TLR4, which is the target of LPS. In conclusion, aloesone demonstrated multiple protective effects against LPS-induced oxidative stress, inflammation, M1 polarization, and apoptosis in macrophages, suggesting its potential as a prodrug.

Bioactive compounds modulating Toll-like 4 receptor (TLR4)-mediated inflammation: pathways involved and future perspectives

Chronic inflammation is associated with the development and progression of several noncommunicable diseases, such as diabetes, cardiovascular disease, chronic kidney disease, cancer, and nonalcoholic fatty liver disease. Evidence suggests that pattern recognition receptors that identify pathogen-associated molecular patterns and danger-associated molecular patterns are crucial in chronic inflammation. Among the pattern recognition receptors, Toll-like receptor 4 (TLR4) stimulates several inflammatory pathway agonists, such as nuclear factor-κB, interferon regulator factor 3, and nod-like receptor pyrin domain containing 3 pathways, which consequently trigger the expression of pro-inflammatory biomarkers, increasing the risk of noncommunicable disease development and progression. Studies have focused on the antagonistic potential of bioactive compounds, following the concept of food as a medicine, in which nutritional strategies may mitigate inflammation via TLR4 modulation. Thus, this review discusses preclinical evidence concerning bioactive compounds from fruit, vegetable, spice, and herb extracts (curcumin, resveratrol, catechin, cinnamaldehyde, emodin, ginsenosides, quercetin, allicin, and caffeine) that may regulate the TLR4 pathway and reduce the inflammatory response. Bioactive compounds can inhibit TLR4-mediated inflammation through gut microbiota modulation, improvement of intestinal permeability, inhibition of lipopolysaccharide-TLR4 binding, and decreasing TLR4 expression by modulation of microRNAs and antioxidant pathways. The responses directly mitigated inflammation, especially nuclear factor-κB activation and inflammatory cytokines release. These findings should be considered for further clinical studies on inflammation-mediated diseases.

Effects of Anthraquinones on Immune Responses and Inflammatory Diseases

The anthraquinones (AQs) and derivatives are widely distributed in nature, including plants, fungi, and insects, with effects of anti-inflammation and anti-oxidation, antibacterial and antiviral, anti-osteoporosis, anti-tumor, etc. Inflammation, including acute and chronic, is a comprehensive response to foreign pathogens under a variety of physiological and pathological processes. AQs could attenuate symptoms and tissue damages through anti-inflammatory or immuno-modulatory effects. The review aims to provide a scientific summary of AQs on immune responses under different pathological conditions, such as digestive diseases, respiratory diseases, central nervous system diseases, etc. It is hoped that the present paper will provide ideas for future studies of the immuno-regulatory effect of AQs and the therapeutic potential for drug development and clinical use of AQs and derivatives.

Aloe-emodin derivative produces anti-atherosclerosis effect by reinforcing AMBRA1-mediated endothelial autophagy

Atherosclerosis is an inflammatory disease of high lethality associated with endothelial dysfunction. Due to the pathophysiological complexity and our incomplete understanding of the mechanisms for the development and progression of atherosclerosis, effective means for the prevention and treatment of atherosclerosis still need further exploration. This study was designed to investigate the potential effects and underlying mechanisms of aloe-emodin derivative (AED) on atherosclerosis. High fat diet (HFD) treated ApoE-/- mice were used as an animal model of atherosclerosis. Intragastric administration of aloe-emodin (AE) or AED for 12 weeks markedly reduced the atherosclerotic plaque in aorta with decreased plaque area, lipid accumulation, macrophage infiltration, collagen content and metabolic abnormalities. By comparison, AED produced more potent anti-atherosclerosis effects than AE at the same dose. AED enhanced production of autophagy flux in cultured human aortic endothelial cells (HAECs). Moreover, AED increased the expression of activating molecule in Beclin1-regulated autophagy 1 (AMBRA1), a key protein involved in autophagosome formation. Furthermore, knockdown of AMBRA1 blocked the promotion effect of AED on autophagy in HAECs. Taken together, AED facilitates endothelial autophagy via AMBRA1 during the progression of atherosclerosis, suggesting the potential application of this compound for atherosclerosis treatment.

LuHui Derivative, A Novel Compound That Inhibits the Fat Mass and Obesity-Associated (FTO), Alleviates the Inflammatory Response and Injury in Hyperlipidemia-Induced Cardiomyopathy

Hyperlipidemia is a major risk factor for metabolic disorders and cardiovascular injury. The excessive deposition of saturated fatty acids in the heart leads to chronic cardiac inflammation, which in turn causes myocardial damage and systolic dysfunction. However, the effective suppression of cardiac inflammation has emerged as a new strategy to reduce the impact of hyperlipidemia on cardiovascular disease. In this study, we identified a novel monomer, known as LuHui Derivative (LHD), which reduced the serum levels of total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and reduced lipid deposition in cardiomyocytes. In addition, LHD treatment improved cardiac function, reduced hyperlipidemia-induced inflammatory infiltration in cardiomyocytes and suppressed the release of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). From a mechanistic perspective, cluster of differentiation 36 (CD36), an important cell surface receptor, was identified as a downstream target following the LHD treatment of palmitic acid-induced inflammation in cardiomyocytes. LHD specifically binds the pocket containing the regulatory sites of RNA methylation in the fat mass and obesity-associated (FTO) protein that is responsible for elevated intracellular m⁶A levels. Moreover, the overexpression of the N6-methyladenosine (m⁶A) demethylase FTO markedly increased CD36 expression and suppressed the anti-inflammatory effects of LHD. Conversely, loss-of-function of FTO inhibited palmitic acid-induced cardiac inflammation and altered CD36 expression by diminishing the stability of CD36 mRNA. Overall, our results provide evidence for the crucial role of LHD in fatty acid-induced cardiomyocyte inflammation and present a new strategy for the treatment of hyperlipidemia and its complications.

Ethyl 2-Succinate-Anthraquinone Attenuates Inflammatory Response and Oxidative Stress via Regulating NLRP3 Signaling Pathway

Aloe-emodin widely possesses antibacterial, anti-inflammatory, antioxidant, antiviral, and anti-infectious properties. This study investigated the effect of ethyl 2-succinate-anthraquinone (Luhui derivative, LHD) on inflammation. In vitro, a THP-1 macrophage inflammation model, made by 100 ng/ml phorbol-12-myristate-13-acetate (PMA) and 1 μg/ml LPS for 24 h, was constructed. The LHD group (6.25 μmol/L, 12.5 μmol/L, 25 μmol/L, 50 μmol/L) had no effect on THP-1 cell activity, and the expression of IL-6 mRNA was down-regulated in a concentration-dependent manner, of which the 25 μmol/L group had the best inhibitory effect. The migration of THP-1 macrophages induced by LPS was decreased by the LHD. Moreover, the LHD suppressed ROS fluorescence expression by inhibiting MDA expression and increasing SOD activity. In vivo, we revealed that the LHD, in different doses (6.25 mg/kg, 12.5 mg/kg, 25 mg/kg, 50 mg/kg), has a protective effect on stress physiological responses by assessing the body temperature of mice. Interestingly, acute lung injury (e.g., the structure of the alveoli disappeared and capillaries in the alveolar wall were dilated and congested) and liver damage (e.g., hepatocyte swelling, neutrophil infiltration, and hepatocyte apoptosis) were obviously improved at the same condition. Furthermore, we initially confirmed that the LHD can down-regulate the expression of NLRP3, IL-1β, and caspase-1 proteins, thereby mediating the NLRP3 inflammasome signaling pathway to produce anti-inflammatory effects. In conclusion, our results indicate that the LHD exerts anti-inflammatory activity via regulating the NLRP3 signaling pathway, inhibition of oxidative stress, and THP-1 macrophage migration.

Inhibition of myeloid differentiation factor 2 attenuates cardiometabolic impairments via reducing cardiac mitochondrial dysfunction, inflammation, apoptosis and ferroptosis in prediabetic rats

Systemic inflammation is a key mediator of left ventricular dysfunction (LV) in prediabetes via the activation of myeloid differentiation factor 2 (MD2)/toll-like receptor 4 complex. The MD2 inhibitor L6H21 effectively reduced systemic and cardiac inflammation in obese mice. However, its effects on cardiac function and regulated cell death pathways in the heart in prediabetes are still unknown. The prediabetic rats were divided into 3 subgroups to receive vehicle, L6H21 (10, 20, 40 mg/kg) or metformin (300 mg/kg) for 1, 2 and 4 weeks. Then, metabolic parameters, cardiac sympathovagal balance, LV function, cardiac mitochondrial function, oxidative stress, inflammation, apoptosis, necroptosis, and ferroptosis were determined. All prediabetic rats exhibited cardiac sympathovagal imbalance, LV dysfunction, and cardiac mitochondrial dysfunction. All doses of L6H21 treatment for 2- and 4-weeks attenuated insulin resistance. L6H21 at 40 mg/kg attenuated cardiac autonomic imbalance and LV dysfunction after 1 week of treatment. Both 10 and 20 mg/kg of L6H21 required longer treatment duration to show these benefits. Mechanistically, all doses of L6H21 reduced cardiac mitochondrial dysfunction after 1 week of treatment, resulting in alleviated oxidative stress and inflammation. L6H21 also effectively suppressed cardiac apoptosis and ferroptosis, but it did not affect necroptosis in prediabetic rats. L6H21 provided the cardioprotective efficacy in dose- and time-dependent manners in prediabetic rats via reduction in apoptosis and ferroptosis.

Anthraquinones from Aloe spp. inhibit Cryptococcus neoformans sensu stricto: effects against growing and mature biofilms

This study aimed to evaluate the in vitro effect of aloe emodin, barbaloin and chrysophanol on growing and mature biofilms of Cryptococcus neoformans sensu stricto. The compounds were added at the moment of inducing biofilm growth or after growth for 72 h to evaluate their effects on growing and mature biofilms, respectively. Then, biofilm biomass was evaluated by crystal violet staining and metabolic activity by the XTT reduction assay. Morphological alterations were also evaluated by laser scanning confocal microscopy. Aloe emodin and barbaloin affected growing biofilms and disrupted mature biofilms, reducing metabolic activity by > 60% and biomass by > 70%. Chrysophanol only inhibited mature biofilms, but to a lesser extent. In conclusion, anthraquinones, especially aloe emodin and barbaloin, show a relevant effect against growing and mature biofilms of C. neoformans sensu stricto.

TGR5 Expression Is Associated with Changes in the Heart and Urinary Bladder of Rats with Metabolic Syndrome

Adipose-derived cytokines may contribute to the inflammation that occurs in metabolic syndrome (MetS). The Takeda G protein-coupled receptor (TGR5) regulates energy expenditure and affects the production of pro-inflammatory biomarkers in metabolic diseases. Etanercept, which acts as a tumor necrosis factor (TNF)-α antagonist, can also block the inflammatory response. Therefore, the interaction between TNF-α and TGR5 expression was investigated in rats with high-fat diet (HFD)-induced obesity. Heart tissues isolated from the HFD-induced MetS rats were analyzed. Changes in TGR5 expression were investigated with lithocholic acid (LCA) as the agonist. Betulinic acid (BA) was used to activate TGR5 in urinary bladders. LCA was more effective in the heart tissues of HFD-fed rats, although etanercept alleviated the function of LCA. STAT3 activation and higher TGR5 expression were observed in the heart tissues collected from HFD-fed rats. Thus, cardiac TGR5 expression is promoted by HFD through STAT3 activation in rats. Moreover, the urinary bladders of female rats fed a HFD showed a low response, which was reversed by etanercept. Relaxation by BA in the bladders was more marked in HFD-fed rats. The high TGR5 expression in HFD-fed rats was characterized using a mRNA assay, and the increased cAMP levels were found to be stimulated by BA in the isolated bladders. Therefore, TGR5 expression increases with a HFD in both the hearts and urinary bladders. Collectively, cytokine-medicated TGR5 activation was observed in the hearts and urinary bladders of rats.

Molecular mechanisms and associated cell signalling pathways underlying the anticancer properties of phytochemical compounds from Aloe species (Review)

Naturally occurring components from various species of Aloe have been used as traditional folk medicine since the ancient times. Over the last few decades, the therapeutic effects of extracts and phytochemical compounds obtained from Aloe vera have been proven in preclinical and clinical studies. Recently, compounds from other Aloe species apart from Aloe vera have been investigated for the treatment of different diseases, with a particular focus on cancer. In the present review, the effects of phytochemical compounds obtained from different Aloe species are discussed, with a specific focus on the effects on cell signalling in cancer and normal cells, and their selectivity and efficacy. This information will be useful for the application of Aloe-derived compounds as therapeutic agents, either alone or in combination with other standard drugs for cancer treatment.

Etanercept Ameliorates Cardiac Fibrosis in Rats with Diet-Induced Obesity

Diet-induced obesity (DIO) is considered the main risk factor for cardiovascular diseases. Increases in the plasma levels of tumor necrosis factor alpha (TNF-α) is associated with DIO. Etanercept, a TNF-α inhibitor, has been shown to alleviate cardiac hypertrophy. To investigate the effect of etanercept on cardiac fibrosis in DIO model, rats on high fat diet (HFD) were subdivided into two groups: the etanercept group and vehicle group. Cardiac injury was identified by classic methods, while fibrosis was characterized by histological analysis of the hearts. Etanercept treatment at 0.8 mg/kg/week twice weekly by subcutaneous injection effectively alleviates the cardiac fibrosis in HFD-fed rats. STAT3 activation seems to be induced in parallel with fibrosis-related gene expression in the hearts of HFD-fed rats. Decreased STAT3 activation plays a role in the etanercept-treated animals. Moreover, fibrosis-related genes are activated by palmitate in parallel with STAT3 activation in H9c2 cells. Etanercept may inhibit the effects of palmitate, but it is less effective than a direct inhibitor of STAT3. Direct inhibition of STAT3 activation by etanercept seems unlikely. Etanercept has the ability to ameliorate cardiac fibrosis through reduction of STAT3 activation after the inhibition of TNF-α and/or its receptor.

Inhibition of TLR4/MAPKs Pathway Contributes to the Protection of Salvianolic Acid A Against Lipotoxicity-Induced Myocardial Damage in Cardiomyocytes and Obese Mice

The occurrence of lipotoxicity during obesity-associated cardiomyopathy is detrimental to health. Salvianolic acid A (SAA), a natural polyphenol extract of Salvia miltiorrhiza Bunge (Danshen in China), is known to be cardioprotective. However, its clinical benefits against obesity-associated cardiomyocyte injuries are unclear. This study aimed at evaluating the protective effects of SAA against lipotoxicity-induced myocardial injury and its underlying mechanisms in high fat diet (HFD)-fed mice and in palmitate-treated cardiomyocyte cells (H9c2). Our analysis of aspartate aminotransferase and creatine kinase isoenzyme-MB (CM-KB) levels revealed that SAA significantly reversed HFD-induced myocardium morphological changes and improved myocardial damage. Salvianolic acid A pretreatment ameliorated palmitic acid-induced myocardial cell death and was accompanied by mitochondrial membrane potential and intracellular reactive oxygen species improvement. Analysis of the underlying mechanisms showed that SAA reversed myocardial TLR4 induction in HFD-fed mice and H9c2 cells. Palmitic acid-induced cell death was significantly reversed by CLI-95, a specific TLR4 inhibitor. TLR4 activation by LPS significantly suppressed SAA-mediated lipotoxicity protection. Additionally, SAA inhibited lipotoxicity-mediated expression of TLR4 target genes, including MyD88 and p-JNK/MAPK in HFD-fed mice and H9c2 cells. However, SAA did not exert any effect on palmitic acid-induced SIRT1 suppression and p-AMPK induction. In conclusion, our data shows that SAA protects against lipotoxicity-induced myocardial damage through a TLR4/MAPKs mediated mechanism.

Effects of REDOX in Regulating and Treatment of Metabolic and Inflammatory Cardiovascular Diseases

Reduction oxidation (REDOX) reaction is crucial in life activities, and its dynamic balance is regulated by ROS. Reactive oxygen species (ROS) is associated with a variety of metabolic diseases involving in multiple cellular signalling in pathologic and physiological signal transduction. ROS are the by-products of numerous enzymatic reactions in various cell compartments, including the cytoplasm, cell membrane, endoplasmic reticulum (ER), mitochondria, and peroxisome. ROS signalling is not only involved in normal physiological processes but also causes metabolic dysfunction and maladaptive responses to inflammatory signals, which depends on the cell type or tissue environment. Excess oxidants are able to alter the normal structure and function of DNA, lipids, and proteins, leading to mutations or oxidative damage. Therefore, excessive oxidative stress is usually regarded as the cause of various pathological conditions, such as cancer, neurodegeneration, cardiovascular diseases (CVDs), diabetes, and kidney diseases. Currently, it has been possible to detect diabetes and other cardiac diseases by detecting derivatives accompanied by oxidative stress in vivo as biomarkers, but there is no effective method to treat these diseases. In consequence, it is essential for us to seek new therapy targeting these diseases through understanding the role of ROS signalling in regulating metabolic activity, inflammatory activation, and cardiac diseases related to metabolic dysfunction. In this review, we summarize the current literature on REDOX and its role in the regulation of cardiac metabolism and inflammation, focusing on ROS, local REDOX signalling pathways, and other mechanisms.

Molecular Mechanisms of Action of Emodin: As an Anti-Cardiovascular Disease Drug

Emodin is a natural occurring anthraquinone derivative isolated from roots and barks of numerous plants, molds, and lichens. It is found to be an active ingredient in different Chinese herbs including Rheum palmatum and Polygonam multiflorum, and it is a pleiotropic molecule with diuretic, vasorelaxant, anti-bacterial, anti-viral, anti-ulcerogenic, anti-inflammatory, and anti-cancer effects. Moreover, emodin has also been shown to have a wide activity of anti-cardiovascular diseases. It is mainly involved in multiple molecular targets such as inflammatory, anti-apoptosis, anti-hypertrophy, anti-fibrosis, anti-oxidative damage, abnormal, and excessive proliferation of smooth muscle cells in cardiovascular diseases. As a new type of cardiovascular disease treatment drug, emodin has broad application prospects. However, a large amount of evidences detailing the effect of emodin on many signaling pathways and cellular functions in cardiovascular disease, the overall understanding of its mechanisms of action remains elusive. In addition, by describing the evidence of the effects of emodin in detail, the toxicity and poor oral bioavailability of mice have been continuously discovered. This review aims to describe a timely overview of emodin related to the treatment of cardiovascular disease. The emphasis is to summarize the pharmacological effects of emodin as an anti-cardiovascular drug, as well as the targets and its potential mechanisms. Furthermore, the treatment of emodin compared with conventional cardiovascular drugs or target inhibitors, the toxicity, pharmacokinetics and derivatives of emodin were discussed.