Glucogallin Attenuates the LPS-Induced Signaling in Macrophages and Protects Mice against Sepsis

Ginsenoside Rb3 represses CPZ-induced demyelination and neuroinflammation by inhibiting TRAF6 K63 ubiquitination

Multiple sclerosis is a chronic inflammatory and neurodegenerative disorder of the central nervous system. Despite ongoing research, effective treatments remain limited, especially during progressive phase. Saponins extracted from the stem and leaf of Panax notoginseng (PNSL) demonstrate a superior anti-inflammatory effect by inhibiting NO production in LPS-induced BV2 cells. Ginsenoside Rb3, the primary active and most abundant component in PNSL, has been demonstrated to mitigate inflammation-induced damage. However, whether Rb3 mitigates demyelination by inhibiting neuroinflammation had not been previously reported. In this study, biochemical and histological assays revealed that ginsenoside Rb3 effectively mitigated Cuprizone-induced demyelination and attenuated aberrant microglial activation and reactive astrogliosis within the demyelinated areas. Mechanistic investigations demonstrated that Rb3 suppresses glial cell activation and consequently mitigates inflammatory responses by inhibiting the secretion of TNF-α, IL-6, and IL-1β. TNF receptor-associated factor 6 (TRAF6) is activated by K63-linked polyubiquitination, which leads to downstream activation of the inhibitor of nuclear factor-κB kinase (IKK) complex and mitogen-activated protein kinases (MAPKs). Furthermore, Rb3 was found to inhibit the activation of nuclear factor-κB (NF-κB) and MAPKs, as evidenced by the dephosphorylation of NF-κB p65 and the MAPKs p38 and JNK. Further investigation revealed that Rb3 binds to TRAF6 at residues 69 and 88, thereby inhibiting its K63-linked polyubiquitination. Conversely, the TRAF6 mutation at E69Q or R88N abolished the inhibition effects of Rb3 on K63-linked ubiquitination of TRAF6 and subsequent downstream signaling activation. Meta-analysis showed that Rb3 exerts its anti-inflammatory effects primarily by inhibiting the NF-κB pathway. Collectively, it is concluded that Rb3 alleviates demyelination and inhibits inflammation through bound to TRAF6 to prevent its K63-linked ubiquitination and subsequent activation of NF-κB. In this study, we have for the first time elucidated that dual mechanism by which Rb3 inhibits both NF-κB and MAPK pathways to exert its anti-inflammatory effects. This study demonstrates that Rb3 shows promising preclinical therapeutic potential. Additionally, TRAF6 represents a potential therapeutic target for MS treatment.

Integration of single-cell RNA sequencing and network pharmacology to elucidate the effect of Yantiao Formula on alleviating ALI by regulating the polarization of alveolar macrophages

ETHNOPHARMACOLOGICAL RELEVANCE

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) has a high mortality rate and often occurs in sepsis. Yantiao Formula (YTF) is used effectively in clinic but its mechanism in the treatment of ALI induced by sepsis remains unelucidated.

AIM OF THE STUDY

This study aims to explore the potential molecular mechanisms of YTF in the treatment of sepsis-induced ALI.

MATERIALS AND METHODS

Using ACQUITY UPLC I-Class, the chemical components contained in YTF were characterized. The network pharmacology approach was used to predict the components and targets of YTF for treating sepsis-induce ALI. Single-cell RNA sequencing (scRNA-seq) was used to find changes in the lung microenvironment after CLP-induced sepsis. Experimental validation was also performed in vitro and in vivo. Using molecular docking, we speculated on the potential pharmacological substances of YTF.

RESULTS

We detected 596 ingredients in YTF and identified 7 absorbed prototypes in serum. 1031 targets for 596 components were retrieved through TCMSP and SwissTargetPrediction databases. 365 potential targets for YTF and sepsis were identified. We observed that the targets of YTF for sepsis were significantly enriched in TNF and chemokine related pathway using GO and KEGG analysis. It was confirmed that at different time points, different doses of YTF increased the CLP-induced PaO2, reduced PaCO2 levels and W/D ratio of lung tissue. CLP- decreased survival rates was also significantly improved by YTF. YTF reversed the increase of IL-6 and IL-1β caused by CLP. Using scRNA-seq analysis, we found that changes in the proportion of cell types and the polarization state of macrophages were evident. Furthermore, the altered levels of biomarkers (M1: IL-1β, iNOS and TNF- α; M2: CD206/Mrc1 and Arg-1) provided evidence of macrophages polarization. We found that CLP-challenged group presented enhanced iNOS and IL-1β expression and YTF increased CD206 and Arg-1 expression in CLP- induced sepsis using immunohistochemical analysis. Similarly, the same results were validated in LPS- induced ALI in NR8383 cells. The material basis and potential therapeutic targets of YTF were also demonstrated using molecular docking.

CONCLUSIONS

YTF reduced the release of inflammatory factors and attenuated sepsis-induced ALI. The combined application of scRNA-seq, network pharmacology and molecular docking was helpful for revealing the mechanism of YTF, which was related to altering levels of M1 and M2 biomarkers to regulate macrophage polarization. The role of YTF in exerting its effects was closely relevant to the potential binding targets of its absorbed prototypes.

The effect of a water-soluble β-glucan on intestinal immunity and microbiota in LPS-challenged piglets

The intestine is the largest immune and barrier organ in the body, and diarrhea and even death during piglet development are related to dysfunction caused by intestinal barrier damage and inflammation. A water-soluble β-glucan produced by Agrobacterium ZX09 has been shown to have a beneficial effect on gastrointestinal health. The main objective of this study was to investigate whether pre-feeding β-glucan has a protective effect on LPS-induced immune stress in piglets. In this study, 24 weaned piglets (21-day-old; 6.64 ± 0.16 kg) were assigned to 4 treatments in a two × two factorial design with diet (with or without β-glucan) and immunological challenge (saline or LPS). Piglets were challenged with saline or LPS after 39 days of feeding 0 or 200 mg/kg β-glucan. The results demonstrated that β-glucan supplementation increased the average daily weight gain and daily feed intake, and decreased diarrhea rate of piglets. Intestinal inflammation symptoms and histological changes in LPS-challenged piglets were alleviated by pre-feeding of β-glucan. β-glucan supplementation reduced serum IL-1β (interleukin-1β) and NO (nitric oxide) secretion in piglets after LPS challenge (0.01 < p < 0.05). Supplementation with β-glucan downregulated the mRNA expression of IL-6 in piglets after LPS challenge (0.01 < p < 0.05). β-glucan supplementation enriched the short-chain fatty acid-producing bacteria, such as Agathobacter and Subdoligranulum (0.01 < p < 0.05), and increased the concentrations of propionate and butyrate (0.01 < p < 0.05). In conclusion, pre-feeding β-glucan can enhance piglet immunity and promote piglet growth by influencing gut microbiota composition and metabolism, and alleviate intestinal damage after LPS challenge.

Effects of Metabolites Derived from Guava (Psidium guajava L.) Leaf Extract Fermented by Limosilactobacillus fermentum on Hepatic Energy Metabolism via SIRT1-PGC1α Signaling in Diabetic Mice

BACKGROUND/OBJECTIVES

Type 2 diabetes mellitus (T2DM) is considered a serious risk to public health since its prevalence is rapidly increasing worldwide despite numerous therapeutics. Insulin resistance in T2DM contributes to chronic inflammation and other metabolic abnormalities that generate fat accumulation in the liver, eventually leading to the progression of metabolic dysfunction-associated fatty liver disease (MAFLD). Recently, the possibility that microbial-derived metabolites may alleviate MAFLD through enterohepatic circulation has emerged, but the underlying mechanism remains unclear. In this research, we utilized metabolites obtained from the fermentation of guava leaf extract, which is well-known for its antidiabetic activity, to investigate their effects and mechanisms on MAFLD.

METHODS

Diabetes was induced by a high-fat diet and streptozotocin injection (80 mg/kg body weight) twice in mice. Subsequently, mice whose fasting blood glucose levels were measured higher than 300 mg/dL were administered with metabolites of Limosilactobacillus fermentum (LF) (50 mg/kg/day) or guava leaf extract fermented by L. fermentum (GFL) (50 mg/kg/day) by gavage for 15 weeks.

RESULTS

GFL supplementation mitigated hyperglycemia and hepatic insulin resistance. Moreover, GFL regulated abnormal hepatic histological changes and lipid profiles in diabetic mice. Furthermore, GFL enhanced energy metabolism by activating the sirtuin1 (SIRT1)/proliferator-activated receptor γ coactivator 1α (PGC1α)/peroxisome proliferator-activated receptor (PPAR)-α pathway in diabetic mice. Meanwhile, GFL supplementation suppressed hepatic inflammation in diabetic mice.

CONCLUSIONS

Taken together, the current study elucidated that GFL could be a potential therapeutic to ameliorate hyperglycemia and hepatic steatosis by improving SIRT1/PGC-1α/ PPAR-α-related energy metabolism in T2DM.

Nanoparticles encapsulated in Abelmoschus esculentus polysaccharide-based pellets as colon targeting approach

AIM(S)

This article explores the application of mesalazine-loaded nanoparticles (MLZ-NPs) encapsulated in Abelmoschus esculentus plant polysaccharide-based pellets (MLZ-NPs-Pellets) for ulcerative colitis.

METHODS

MLZ-NPs were prepared and evaluated for diameter, PDI, and entrapment efficiency. In-vitro efficacy study was conducted on Caco-2 cells. MLZ-NPs were encapsulated in polysaccharides to form MLZ-NPs-Pellets and characterised for efficacy in animals and targeting efficiency in human volunteers.

RESULTS

Optimised batch of MLZ-NPs were characterised for diameter, PDI, zeta potential and entrapment efficiency which was found to be 145.42 ± 6.75 nm, 0.214 ± 0.049, -31.63 mV and 77.65 ± 2.33(%w/w) respectively. ROS, superoxide and NF-kβ were well controlled in Caco-2 cells when treated with MLZ-NPs. In-vivo data revealed that some parameters (body weight, colon length, lipid peroxidase, and glutathione) recovered significantly in the DSS-induced mice model treated with oral MLZ-NPs-Pellets. Gamma scintigraphy revealed that the formulation can effectively target the colon within 600 min.

CONCLUSION

MLZ-NPs-Pellets can be effectively used for microbial-triggered colon targeting approach in treating ulcerative colitis.

Thiazolidine-2,4-dione hybrids as dual alpha-amylase and alpha-glucosidase inhibitors: design, synthesis, in vitro and in vivo anti-diabetic evaluation

Twelve 3,5-disubstituted-thiazolidine-2,4-dione (TZD) hybrids were synthesized using solution phase chemistry. Continuing our previous work, nine O-modified ethyl vanillin (8a-i) derivatives were synthesized and reacted with the TZD core via Knoevenagel condensation under primary reaction conditions to obtain final derivatives 9a-i. Additionally, three isatin-TZD hybrids (11a-c) were synthesized. The intermediates and final derivatives were characterized using 1H and 13C NMR spectroscopy, and the observed chemical shifts agreed with the proposed structures. The in vitro alpha-amylase and alpha-glucosidase inhibitory evaluation of newly synthesized derivatives revealed compounds 9F and 9G as the best dual inhibitors, with IC50 values of 9.8 ± 0.047 μM for alpha-glucosidase (9F) and 5.15 ± 0.0017 μM for alpha-glucosidase (9G), 17.10 ± 0.015 μM for alpha-amylase (9F), and 9.2 ± 0.092 μM for alpha-amylase (9G). The docking analysis of synthesized compounds indicated that compounds have a higher binding affinity for alpha-glucosidase as compared to alpha-amylase, as seen from docking scores ranging from -1.202 to -5.467 (for alpha-amylase) and -4.373 to -7.300 (for alpha-glucosidase). Further, the molecules possess a high LD50 value, typically ranging from 1000 to 1600 mg kg-1 of body weight, and exhibit non-toxic properties. The in vitro cytotoxicity assay results on PANC-1 and INS-1 cells demonstrated that the compounds were devoid of significant toxicity against the tested cells. Compounds 9F and 9G showed high oral absorption, i.e., oral absorption >96%, and their molecular dynamics simulation yielded results closely aligned with the observed docking outcomes. Finally, compounds 9F and 9G were evaluated for in vivo antidiabetic assessment by the induction of diabetes in Wistar rats using streptozotocin. Molecule 9G has been identified as the most effective anti-diabetic molecule due to its ability to modulate several biochemical markers in blood plasma and tissue homogenates. The results were further confirmed by histology investigations conducted on isolated pancreas, liver, and kidney.

Natural products act as game-changer potentially in treatment and management of sepsis-mediated inflammation: A clinical perspective

BACKGROUND

Sepsis, a life-threatening condition resulting from uncontrolled host responses to infection, poses a global health challenge with limited therapeutic options. Due to high heterogeneity, sepsis lacks specific therapeutic drugs. Additionally, there remains a significant gap in the clinical management of sepsis regarding personalized and precise medicine.

PURPOSE

This review critically examines the scientific landscape surrounding natural products in sepsis and sepsis-mediated inflammation, highlighting their clinical potential.

METHODS

Following the PRISMA guidelines, we retrieved articles from PubMed to explore potential natural products with therapeutic effects in sepsis-mediated inflammation.

RESULTS

434 relevant in vitro and in vivo studies were identified and screened. Ultimately, 55 studies were obtained as the supporting resources for the present review. We divided the 55 natural products into three categories: those influencing the synthesis of inflammatory factors, those affecting surface receptors and modulatory factors, and those influencing signaling pathways and the inflammatory cascade.

CONCLUSION

Natural products' potential as game-changers in sepsis-mediated inflammation management lies in their ability to modulate hallmarks in sepsis, including inflammation, immunity, and coagulopathy, which provides new therapeutic avenues that are readily accessible and capable of undergoing rapid clinical validation and deployment, offering a gift from nature to humanity. Innovative techniques like bioinformatics, metabolomics, and systems biology offer promising solutions to overcome these obstacles and facilitate the development of natural product-based therapeutics, holding promise for personalized and precise sepsis management and improving patient outcomes. However, standardization, bioavailability, and safety challenges arise during experimental validation and clinical trials of natural products.

Advances in molecular agents targeting toll-like receptor 4 signaling pathways for potential treatment of sepsis

Sepsis is a systemic inflammatory response syndrome caused by an infection. Toll-like receptor 4 (TLR4) is activated by endogenous molecules released by injured or necrotic tissues. Additionally, TLR4 is remarkably sensitive to infection of various bacteria and can rapidly stimulate host defense responses. The TLR4 signaling pathway plays an important role in sepsis by activating the inflammatory response. Accordingly, as part of efforts to improve the inflammatory response and survival rate of patients with sepsis, several drugs have been developed to regulate the inflammatory signaling pathways mediated by TLR4. Inhibition of TLR4 signal transduction can be directed toward either TLR4 directly or other proteins in the TLR4 signaling pathway. Here, we review the advances in the development of small-molecule agents and peptides targeting regulation of the TLR4 signaling pathway, which are characterized according to their structural characteristics as polyphenols, terpenoids, steroids, antibiotics, anthraquinones, inorganic compounds, and others. Therefore, regulating the expression of the TLR4 signaling pathway and modulating its effects has broad prospects as a target for the treatment of lung, liver, kidneys, and other important organs injury in sepsis.

Phytol from Scoparia dulcis prevents NF-κB-mediated inflammatory responses during macrophage polarization

Macrophages are primary immune cells that mediate a wide range of inflammatory diseases through their polarization potential. In this study, phytol isolated from Scoparia dulcis has been explored against 7-ketocholesterol and bacterial lipopolysaccharide-induced macrophage polarization in IC-21 cells. Isolated phytol has been characterized using GC-MS, TLC, HPTLC, FTIR, 1H-NMR, and HPLC analyses. The immunomodulatory effects of viable concentrations of phytol were tested on oxidative stress, arginase activity, nuclear and mitochondrial membrane potentials in IC-21 cells in addition to the modulation of calcium and lipids. Further, gene and protein expression of atherogenic markers were studied. Results showed that the isolated phytol at a viable concentration of 400 µg/ml effectively reduced the production of nitric oxide, superoxide anion (ROS generation), calcium and lipid accumulation, stabilized nuclear and mitochondrial membranes, and increased arginase activity. The atherogenic markers including iNOS, COX-2, IL-6, IL-1β, MMP-9, CD36, and NF-κB were significantly downregulated at the levels of gene and protein expression, while macrophage surface and nuclear receptor markers (CD206, CD163, and PPAR-γ) were significantly upregulated by phytol pre-treatment in macrophages. Therefore, the present pharmacognostic study supports the role of phytol isolated from Scoparia dulcis in preventing M2-M1 macrophage polarization under inflammatory conditions, making it a promising compound.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-024-03924-9.

3,5-Disubstituted-thiazolidine-2,4-dione hybrids as antidiabetic agents: Design, synthesis, in-vitro and In vivo evaluation

Diabetes is one of the fastest-growing metabolic disorders, nearly doubling the number of patients each year. There are different treatment approaches available for the management of diabetes, which lacks due to their side effects. The inhibition of enzymes involved in the metabolism of complex polysaccharides to monosaccharides has proven beneficial in patients with type 2 diabetes mellitus. Two enzymes, α-amylase and α-glucosidase, have emerged as potential drug targets and are widely explored for drug development against type 2 diabetes mellitus. In this context, thiazolidine-2,4-diones (TZDs) have emerged as potential drug candidates for developing newer molecules against α-amylase and α-glucosidase. Nineteen TZD-hybrids were synthesized and evaluated in vitro α-amylase and α-glucosidase inhibitory activity. The compounds 7i, 7k, and 7p have emerged as the best dual inhibitors with IC50 of 10.33 ± 0.11-20.94 ± 0.76 μM and 10.19 ± 0.25-24.07 ± 1.56 μM against α-glucosidase and α-amylase, respectively. The derivatives had good anti-oxidant activity, displaying IC50 = 14.95 ± 0.65-23.27 ± 0.99 μM. The compounds 7k and 7p showed the best inhibition of reactive oxygen species in the PNAC-1 cells. The molecules exhibit good binding within the active site of α-amylase (PDB id: 1B2Y) and α-glucosidase (PDB id: 3W37), displaying binding energies of -7.5 to -10.7 kcal/mol and -7.4 to -10.3 kcal/mol, respectively. Further, the compounds were nontoxic (LD50 = 500-1311 mg/kg) and possessed good GI absorption. The compounds 7i, 7k, and 7p were evaluated in vivo antidiabetic activity in an STZ-induced diabetic model in Wistar rats. The compound 7p emerged as the best compound in the in vivo studies; however, the activity was lesser than that of the standard drug pioglitazone.

Investigation of the anti-cancer potential of epoxyazadiradione in neuroblastoma: experimental assays and molecular analysis

Neuroblastoma, the most common childhood solid tumor, originates from primitive sympathetic nervous system cells. Epoxyazadiradione (EAD) is a limonoid derived from Azadirachta indica, belonging to the family Meliaceae. In this study, we isolated the EAD from Azadirachta indica seed and studied the anti-cancer potential against neuroblastoma. Herein, EAD demonstrated significant efficacy against neuroblastoma by suppressing cell proliferation, enhancing the rate of apoptosis and cycle arrest at the SubG0 and G2/M phases. EAD enhanced the pro-apoptotic Caspase 3 and Caspase 9 and inhibited the NF-kβ translocation in a dose-dependent manner. In order to identify the specific EAD target, a gel-free quantitative proteomics study on SH-SY5Y cells using Liquid Chromatography with tandem mass spectrometry was done in a dose-dependent manner, followed by detailed bioinformatics analysis to identify effects on protein. Proteomics data identified that Enolase1 and HSP90 were up-regulated in neuroblastoma. EAD inhibited the expression of Enolase1 and HSP90, validated by mRNA expression, immunoblotting, Enolase1 and HSP90 kit and flow-cytometry based bioassay. Molecular docking study, Molecular dynamic simulation, and along with molecular mechanics/Poisson-Boltzmann surface area analysis also suggested that EAD binds at the active site of the proteins and were stable throughout the 100 ns Molecular dynamic simulation study. Overall, this study suggested EAD exhibited anti-cancer activity against neuroblastoma by targeting Enolase1 and HSP90 pathways.Communicated by Ramaswamy H. Sarma.

Molecular Cloning, Expression, and Functional Analysis of Glycosyltransferase (TbUGGT) Gene from Trapa bispinosa Roxb

Trapa bispinosa Roxb. is an economical crop for medicine and food. Its roots, stems, leaves, and pulp have medicinal applications, and its shell is rich in active ingredients and is considered to have a high medicinal value. One of the main functional components of the Trapa bispinosa Roxb. shell is 1-galloyl-beta-D-glucose (βG), which can be used in medical treatment and is also an essential substrate for synthesizing the anticancer drug beta-penta-o-Galloyl-glucosen (PGG). Furthermore, gallate 1-beta-glucosyltransferase (EC 2.4.1.136) has been found to catalyze gallic acid (GA) and uridine diphosphate glucose (UDPG) to synthesize βG. In our previous study, significant differences in βG content were observed in different tissues of Trapa bispinosa Roxb. In this study, Trapa bispinosa Roxb. was used to clone 1500 bp of the UGGT gene, which was named TbUGGT, to encode 499 amino acids. According to the specificity of the endogenous expression of foreign genes in Escherichia coli, the adaptation codon of the cloned original genes was optimized for improved expression. Bioinformatic and phylogenetic tree analyses revealed the high homology of TbUGGT with squalene synthases from other plants. The TbUGGT gene was constructed into a PET-28a expression vector and then transferred into Escherichia coli Transsetta (DE3) for expression. The recombinant protein had a molecular weight of 55 kDa and was detected using SDS-PAGE. The proteins were purified using multiple fermentation cultures to simulate the intracellular environment, and a substrate was added for in vitro reaction. After the enzymatic reaction, the levels of βG in the product were analyzed using HPLC and LC-MS, indicating the catalytic activity of TbUGGT. The cloning and functional analysis of TbUGGT may lay the foundation for further study on the complete synthesis of βG in E. coli.