The present study examined the potential neuroprotective effects of aloe-emodin (AE) nanoparticles on the cerebral stroke-associated target protein myeloperoxidase (MPO). We investigated the binding interactions between AE and MPO through molecular docking and molecular dynamics simulations. Molecular docking results indicated that AE exhibited a binding energy of -6.9 kcal/mol, whereas it was -7.7 kcal/mol for 2-{[3,5-bis(trifluoromethyl)benzyl]amino}-n-hydroxy-6-oxo-1,6-dihydropyrimidine-5-carboxamide (CCl). Furthermore, molecular dynamics studies demonstrated that AE possesses a stronger binding affinity (-57.137 ± 13.198 kJ/mol) than does CCl (-22.793 ± 30.727 kJ/mol), suggesting that AE has a more substantial inhibitory effect on MPO than does CCl. Despite the therapeutic potential of AE for neurodegenerative disorders, its bioavailability is limited within the body. A proposed hypothesis to enhance the bioavailability of AE is its conversion into aloe-emodin nanoparticles (AENP). The AENPs synthesized through a fabrication method were spherical with a consistent diameter of 104.4 ± 7.9 nm and a polydispersity index ranging from 0.525 to 0.586. In rats experiencing cerebral stroke, there was a notable increase in cerebral infarction size; abnormalities in electrocardiogram (ECG) and electroencephalogram (EEG) patterns; a decrease in brain and cardiac antioxidant activities; and an increase in myeloperoxidase levels compared to those in normal rats. Compared with AE treatment, AENP treatment significantly ameliorated cerebral infarction, normalized ECG and EEG patterns, enhanced brain and cardiac antioxidant activities, and reduced MPO levels in stroke rats. Histopathological evaluations revealed pronounced alterations in the rat hippocampus, with pyknotic nuclei, disarray and loosely packed cells, deterioration of cardiac muscle fibers, and extensive damage to cardiac myocytes, in contrast to those in normal rats. AENP treatment mitigated these pathological changes more effectively than AE treatment in both brain and cardiac cells. These findings support that AENP provides considerable protection against stroke-associated myocardial infarction.

To improve patient survival in sepsis, it is necessary to curtail exaggerated inflammatory responses. Fucoxanthin (FX), a carotenoid derived from brown algae, efficiently suppresses pro-inflammatory cytokine expression via IRF3 activation, thereby reducing mortality in a mouse model of sepsis. However, the effects of FX-targeted IRF3 on the bacterial flora (which is disrupted in sepsis) and the mechanisms by which it impacts sepsis development remain unclear. This study aims to elucidate how FX-targeted IRF3 modulates intestinal microbiota compositions, influencing sepsis development. FX significantly reduced the bacterial load in the abdominal cavity of mice with cecal ligation and puncture (CLP)-induced sepsis via IRF3 activation and increased short-chain fatty acids, like acetic and propionic acids, with respect to their intestines. FX also altered the structure of the intestinal flora, notably elevating beneficial Verrucomicrobiota and Akkermansia spp. while reducing harmful Morganella spp. Investigating the inflammation-flora link, we found positive correlations between the abundances of Morganella spp., Proteus spp., Escherichia spp., and Klebsiella spp. and pro-inflammatory cytokines (IL-6, IL-1β, and TNF-α) induced by CLP. These bacteria were negatively correlated with acetic and propionic acid production. FX alters microbial diversity and promotes short-chain fatty acid production in mice with CLP-induced sepsis, reshaping gut homeostasis. These findings support the value of FX for the treatment of sepsis.

BACKGROUND: Emodin is a natural bioactive ingredient mainly extracted from traditional Chinese herbs. Increasing lines of evidence suggest that emodin and its analogs exert notable synergistic pharmacological effects with other bioactive compounds.
OBJECTIVE: This review provides an overview of the pharmacological activity of emodin and its analogs in combination with other physiologically active substances, describes the related molecular mechanisms, and discusses future prospects in this field.
METHODS: Information from multiple scientific databases, such as PubMed, the China Knowledge Resource Integrated Database from the China National Knowledge Infrastructure (CNKI), the Web of Science, Google Scholar, and Baidu Scholar, was collected between January 2006 and August 2022. The subject terms used in the literature search were emodin, pharmaceutical activities, analogs, aloe emodin, rhein, and synergistic effects.
RESULTS: The comprehensive literature analysis suggested that combinations of emodin or its analogs with other bioactive compounds exert notable synergistic anticancer, anti-inflammatory, and antimicrobial effects and that such combinations improve glucose and lipid metabolism and central nervous system diseases.
CONCLUSIONS: Further assessments of the dose-effect relationship and the differences in the efficacy of emodin or its analogs with other bioactive compounds among various modes of administration are needed, and a drug safety evaluation of these combinations needs to be carefully performed. Future studies should also focus on determining the optimal drug combinations for specific diseases.

BACKGROUND: High-performance thin-layer chromatography (HPTLC) was developed and validated for the determination of aloe-emodin in accordance with ICH guidelines. In addition, a novel RP-UHPLC method was developed, and both methods were used to analyse the herbal extract and herbal formulation.
METHODS: Separation was carried out on a silica gel 60 F254 HPTLC plate using the mobile phase Toluene: Methanol (9:1). The linearity was good across the 800-4000 ng/spot range. Validation results are within acceptable limits. The percent RSD for accuracy was 0.58-1.77, and precision was 1.10-1.97 and 1.45-1.94 for intraday and interday, respectively. The percentage of aloe-emodin found in the herbal extract and aloe vera capsule was 99.83 ± 1.19 and 99.53 ± 1.29, respectively, using this method.
RESULTS: Quantification of aloe-emodin in herbal extract and herbal formulation were done using a novel UHPLC method with chromatographic conditions of orthophosphoric acid Methanol (0.1 percent OPA): Water (65:35, v/v) and pH 3, a flow rate of 1.2 ml/min, and elute detection at 254 nm. At 6.32 minutes, a sharp and symmetric peak was observed. The method developed was validated in accordance with ICH guidelines. The percent RSD numerical value of accuracy was 0.304-0.576, and the inter-day and intraday precision were 0.32-3.08 and 0.51-2.78, respectively. Herbal extract and aloe vera capsule were analysed using the new UHPLC method. Aloe-emodin percentages were reported as 100.3 ± 0.89 and 99.53 ± 1.29, respectively.
CONCLUSIONS: The antimicrobial and anti-oxidant activities of an aloe-vera herbal formulation were studied, and the results were positive.

Oral squamous cell carcinoma (OSCC) is one of the most prevalent cancers worldwide, especially in Asian countries. The emergence of its drug resistance and its side effects demands alternatives, to improve prognosis. Since the majority of cancer drugs are derived from natural sources, it provides a window to look for more biocompatible alternatives. In this study, two natural compounds, costunolide (CE) and aloe emodin (AE), were isolated from the stem of Lycium shawii. The compounds were examined for their anticancer and apoptotic potentials against OSCC (CAL 27) cells, using an in vitro analysis, such as a MTT assay, scratch assay, gene, and protein expressions. Both compounds, CE and AE, were found to be cytotoxic against the cancer cells with an IC50 value of 32 and 38 µM, respectively. Moreover, the compounds were found to be non-toxic against normal NIH-3T3 cells and comparable with the standard drug i.e., 5-fluorouracil (IC50 = 97.76 µM). These compounds were active against normal cells at higher concentrations. Nuclear staining displayed the presence of apoptosis-associated morphological changes, i.e., karyopyknosis and karyorrhexis in the treated cancer cells. Flow cytometry results further confirmed that these compounds induce apoptosis rather than necrosis, as the majority of the cells were found in the late apoptotic phase. Gene and protein expression analyses showed an increased expression of apoptotic genes, i.e., BAK, caspase 3, 6, and 9. Moreover, the compounds significantly downregulated the expression of the anti-apoptotic (BCL-2 L1), metastatic (MMP-2), and pro-inflammatory (COX-2) genes. Both compounds have shown promising anticancer, apoptotic, and anti-migratory activities against the OSCC cell line (i.e., CAL-27). However, further in vivo studies are required to explore these compounds as anticancer agents.

Cationic water-based polyurethane(CWPU) was synthesized to explore aloe-emodin modifies to obtain CWPU materials with better comprehensive performance. It provides a simple way to synthesize antibacterial waterborne polyurethane, which is to introduce the end-blocking group of herbal extracts into the structure. It contains synergistic antibacterial effect of herbal antibacterial and quaternary ammonium ion on Escherichia coli. It makes the material resist the erosion of bacterial, and increase the service life of materials. When the pH value of the environment changes, the UV absorbance of the aloe-emodin modified cationic water-based polyurethane(AE-CWPU) also changes. Therefore, within a certain detection range, AE-CWPU has great applications in the field of smart response materials. The modified thermodynamic properties have been improved, and the mechanical properties basically maintained the maximum stress, and the elongation at break was reduced.

Aloe emodin-conjugated sulfonyl hydrazones were designed and synthesized as novel type of antibacterial modulators. Aloe emodin benzenesulfonyl hydrazone 5a (AEBH-5a) was preponderant for the treatment of S. aureus 25923 (MIC = 0.5 μg/mL) over norfloxacin and presented high selectivity between bacterial membranes and mammalian membranes. Especially, AEBH-5a could eliminate the formed biofilms and relieve the development of S. aureus 25923 resistance. The antibacterial mechanism of AEBH-5a from extracellularity to intracellularity illustrated that AEBH-5a could destroy bacterial membrane integrity, leading to the leakage of protein and nucleic acid. Besides, AEBH-5a could not only interact with DNA and induce oxidative stress but also inhibit lactate dehydrogenase (LDH) activity as well as render metabolic inactivation. In silico ADME studies prediction of AEBH-5a revealed a favorable bioavailability score and prominent drug-likeness profile. This research showed that the multifaceted synergistic effect initiated by aloe emodin-conjugated sulfonyl hydrazones is a reasonable and effective tactic to combat menacing bacterial infections.

Plants contain underutilized resources of compounds that can be employed to combat viral diseases. Aloe vera (L.) Burm. f. (syn. Aloe barbadensis Mill.) has a long history of use in traditional medicine, and A. vera extracts have been reported to possess a huge breadth of pharmacological activities. Here, we discuss the potential of A. vera compounds as antivirals and immunomodulators for the treatment of viral diseases. In particular, we highlight the use of aloe emodin and acemannan as lead compounds that should be considered for further development in the management and prevention of viral diseases. Given the immunomodulatory capacity of A. vera compounds, especially those found in Aloe gel, we also put forward the idea that these compounds should be considered as adjuvants for viral vaccines. Lastly, we present some of the current limitations to the clinical applications of compounds from Aloe, especially from A. vera.

The dramatic rise in drug resistance accelerated the desire for new antibacterial agents to safeguard human health. This work constructed a novel type of aloe emodin-hybridized sulfonamide aminophosphates as unique potential antibacterial agents. The biological assay revealed that some target hybrids possessed potent inhibitory activity. Particularly, ethyl aminophosphate-hybridized sulfadiazine aloe emodin 7a (EASA-7a) not only displayed preponderant antibacterial efficiency against drug-resistant E. faecalis at low concentration as 0.25 μg/mL but also possessed strong bacteriostatic capacity and low propensity to develop resistance toward E. faecalis. The weak hemolysis toward human red blood cells and efficient biofilm-disruptive ability further implied the therapeutic potential of EASA-7a. Preliminary studies disclosed that the excellent antibacterial behavior of EASA-7a might be attributed to its capacity to permeate and depolarize the bacterial membrane, as well as promote ROS accumulation and intercalate with DNA. These findings manifested that EASA-7a was worthy of further development to combat life-threatening bacterial infections.

The anti-inflammatory effects of Aloe vera (AV), polysaccharide extract from AV, and extracts from the digestion and colonic fermentation of AV were evaluated using an immortal astrocyte cell line (U373 MG) that develops a neuro-inflammatory profile. Cell viability and inflammatory markers were assessed after stimulation with neuropeptide substance P (SP) that activates the pro-inflammatory MAPK (mitogen-activated protein kinase) pathway. Cell viability after SP treatment was over 50% at 10 mg/mL AV, polysaccharide extract from AV, extracts from the digestion: non-digestible fraction of AV non-digestible fraction of polysaccharide extract from AV and extracts from the colonic fermentation of AV, at 4 and 24 h. Moreover, cells exposed to SP and treated with these extracts showed lower protein-activated ERK1/ERK2 (extracellular signal-regulated kinases 1 and 2), p38 (MAPK protein p38), and NFκB (nuclear factor κB) levels with respect to the SP-stimulated control. Inflammation inhibition by extracts of polysaccharide extract from AV and extracts from the colonic fermentation of AV, at 24 h in the study of p38 was not as statistically significant in ERK1/ERK2 and NFκB. Nevertheless, there was a significant decrease (p < 0.05) in pro-inflammatory cytokine IL-6 levels in cells exposed to all samples. Samples with extracts from the colonic fermentation of AV, at 4 or 24 h showed the highest inhibitory effect on IL-6 production.