Anti-inflammatory function of 4-tert-butylphenyl salicylate through down-regulation of the NF-kappa B pathway

Modified huangfeng decoction alleviates diabetic nephropathy by activating autophagy and regulating the gut microbiota

BACKGROUND

Diabetic nephropathy (DN) is one of the complications with the highest mortality among diabetes patients and can lead to renal failure. Modified Huangfeng decoction (MHD) has been widely applied in the clinical treatment of kidney diseases. However, the mechanism by which MHD affects DN has not been fully elucidated.

PURPOSE

To investigate the impact of MHD on DN in mice and the underlying mechanism.

METHODS

The main ingredients of MHD were identified by liquid chromatography‒mass spectrometry. A high-fat diet- and streptozotocin (STZ)-induced DN mouse model was constructed and treated with MHD for 6 weeks. The serum and urine parameters were measured, and the tissue sections were histologically stained. The mRNA and protein levels of metabolism-, inflammation-, fibrosis-, and autophagy-related markers were examined by qPCR and western blotting. The microbial composition and metabolites of cecal contents were analyzed through full-length 16S rRNA sequencing and nontargeted metabolomics.

RESULTS

MHD alleviated insulin resistance in DN mice and ameliorated changes in lipid metabolism and inflammation in the liver and fat. In addition, MHD reduced the levels of kidney injury markers in the serum and urine and attenuated inflammation and fibrosis in the kidney. These results were accompanied by enhanced gut barrier function and a markedly altered microbiota composition and metabolites, with an increased abundance of beneficial bacterial species and metabolites. Moreover, MHD itself and the microbial metabolite spermidine reduced podocyte damage by activating autophagy via the PI3K/AKT/mTOR pathway.

CONCLUSIONS

MHD potentially ameliorated DN by activating podocyte autophagy via the PI3K/AKT/mTOR pathway and modulating the gut microbiota and its metabolites. Our findings provide a more comprehensive understanding of the mechanism of MHD and the involvement of the gut‒kidney interaction in the progression of DN, laying a theoretical foundation for the clinical application of MHD in DN treatment.

Triptolide Suppressed the Microglia Activation to Improve Spinal Cord Injury Through miR-96/IKKβ/NF-κB Pathway

STUDY DESIGN

The effect of triptolide on spinal cord injury (SCI) and inflammatory response was observed by establishing SCI rat model. And in vitro experiments were conducted to determine the underlying mechanism of triptolide-mediated in murine microglial cell line BV2.

OBJECTIVE

To determine the underlying mechanism of triptolide in suppressing the microglia activation to improve SCI.

SUMMARY OF BACKGROUND DATA

Triptolide, as a major active ingredient of Chinese herb Tripterygium wilfordii, can promote spinal cord repair through inhibiting microglia activation, but the underlying mechanism is not clear.

METHODS

Locomotion recovery was accessed by Basso, Beattie, and Bresnahan score, the number of footfalls, stride length, and angle of rotation analysis. Expressions of microRNA 96 (miR-96), microglia activation marker Iba-1, and IκB kinase (IKKβ)/nuclear factor (NF)-κB-related proteins were detected by qRT-PCR or western blot. Inflammatory cytokines tumor necrosis factor-α and interleukin -1β were measured by enzyme-linked immuno sorbent assay. The regulation of miR-96 on IKKβ was confirmed by dual luciferase reporter assay.

RESULTS

Triptolide promoted locomotion recovery of SCI rats, upregulated the expression of miR-96, decreased microglia activation marker Iba-1 and IKKβ/NF-κB-related proteins, and inhibited inflammatory cytokines tumor necrosis factor-α and interleukin-1β levels in spinal cord tissues and lipopolysaccharide -induced microglia. Triptolide suppressed the microglia activation and inflammatory cytokines secretion in BV2 cells through up-regulating miR-96. We confirmed the interaction between miR-96 and IKKβ, and IKKβ expression was negatively regulated by miR-96. Finally, we determined that triptolide suppressed the microglia activation and inflammatory cytokines secretion through miR-96/IKKβ pathway.

CONCLUSION

Triptolide suppressed microglia activation after SCI through miR-96/IKKβ/NF-κB pathway.

LEVEL OF EVIDENCE

N/A.

Glycin-rich antimicrobial peptide YD1 from B. amyloliquefaciens, induced morphological alteration in and showed affinity for plasmid DNA of E. coli

Antimicrobial peptides (AMPs), low-molecular-weight proteins with broad-spectrum antimicrobial activity, are the most promising candidates for the development of novel antimicrobials. A powerful cationic glycine-rich AMP YD1 (MW ~ 1.0 kDa) was purified from Bacillus amyloliquefaciens CBSYD1 isolated from traditional Korean fermented food kimchi, for the treatment of multidrug-resistant (MDR) bacteria. Strain CBSYD1 was identified 99.79% similar to Bacillus amyloliquefaciens subsp. plantarum FZB42(T) by 16S rRNA sequence analysis. The amino acid sequence residues of YD1 were determined to be Ala-Pro-Lys-Gly-Val-Gln-Gly-Pro-Asn-Gly by Edman degradation method. After the analysis and comparison of YD1 peptide sequence using several bioinformatic servers, peptide sequence has been considered to be unique. YD1 displayed antimicrobial activity against gram-positive and gram-negative bacteria. The minimal inhibitory concentrations (MIC) of YD1 for Escherichia coli KCTC1923 (E. coli), methicillin-resistant Staphylococcus aureus B15 (MRSA), and vancomycin-resistant enterococci (VRE) ranged from 8 to 64 µg/mL, representing greater potency than commercial reference antibiotics. The antimicrobial mechanism of YD1 was determined to involve cell-penetrating translocation inside the cell and interaction with the DNA leading ultimately to bacterial cell death. Analogously, Gly-Pro-Asn-Gly is the likely expected cell-penetrating motif for YD1. YD1 could be a promising antimicrobial agent for the clinical application.

A novel multifunctional peptide oligomer of bacitracin with possible bioindustrial and therapeutic applications from a Korean food-source Bacillus strain

Investigating the effects of a multifunctional microbial peptide possessing strong anti-inflammatory activity against pathogenic bacteria. The antimicrobial activity of the purified peptide (CSP32) against various multidrug-resistant as well as anaerobic pathogens was determined. Anti-inflammatory activity was determined by an enzyme-linked immunosorbent assay, western blotting, and RT-PCR in RAW 264.7 macrophages. Molecular weight and structural elucidation were performed by several analytical methods such as mass spectrometry and chemoinformatic analysis. CSP32, purified from newly isolated Bacillus sp. CS32, was active against methicillin-resistant Staphylococcus aureus, vancomycin-resistant S. aureus, vancomycin-resistant enterococci, and anaerobic pathogens Propionibacterium acne and Clostridium difficile. Furthermore, CSP32 showed strong inhibitory effects on lipopolysaccharide (LPS)-induced nitric oxide (NO) production and nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) expression in RAW 264.7 macrophages. At concentrations of 10, 50, and 100 μg/mL, CSP32 treatment attenuated LPS-induced expression of nuclear factor kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) as well as other proinflammatory mediators such as tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), and IL-1β. CSP32 potently inhibited translocation of NF-κB into the nucleus by suppressing degradation of IκB kinase (IκBα) and its phosphorylation, thereby causing NF-κB to remain inactive. CSP32 may be the first oligomer of bacitracin with anti-inflammatory properties.

Deguelin Attenuates Allergic Airway Inflammation via Inhibition of NF-κb Pathway in Mice

Asthma is a chronic respiratory disease characterized by airway inflammation and remodeling, resulting in a substantial economic burden on both patients and society. Deguelin, a constituent of the Leguminosae family, exhibits anti-proliferative and anti-inflammatory activities in cancer mice models via inhibiting phosphatidylinositol 3-kinases and the NF-κB pathway. We demonstrated that deguelin effectively reduced OVA-induced inflammatory cell recruitment, decreased lung tissue inflammation and mucus production, suppressed airway hyperresponsiveness, and inhibited serum immunoglobulin and Th2 cytokine levels in a dose-dependent manner in asthmatic mice. In addition, we found that deguelin reduced inflammatory gene expressions both in vivo and in vitro, which were closely associated with activation of the NF-κB signaling pathway. Thus, we further explored the underlying mechanisms of deguelin in normal human bronchial epithelial cells (BEAS-2B). Our results suggested that deguelin inhibited NF-κB binding activity by enhancing the ability of IκBα to maintain NF-κB in an inactive form in the cytoplasm and preventing the TNF-α induced translocation of p65 to the nucleus. In conclusion, our research indicates that deguelin attenuates allergic airway inflammation via inhibition of NF-κB pathway in mice model and may act as a potential therapeutic agent for patients with allergic airway inflammation.