Protective effect of α–lipoic acid against spleen toxicity of dimethylnitrosamine in male mice: Antioxidant and ultrastructure approaches

Poria cocos oligosaccharides ameliorate dextran sodium sulfate-induced colitis mice by regulating gut microbiota dysbiosis

Poria cocos, a widely accepted function food in China, has multiple pharmacological activities. This study aimed to investigate the therapeutic effect and molecular mechanism of Poria cocos oligosaccharides (PCOs) against dextran sodium sulfate (DSS)-induced mouse colitis. In this study, BALB/c mice were treated with 3% (w/v) DSS for seven days to establish a colitis model. The results showed that oral administration of PCOs (200 mg per kg per day) significantly reversed the changes in the physiological indices in colitis mice, including body weight, disease activity index scores (DAI), spleen index, and colon length. From the qRT-PCR assay, it was observed that PCOs suppressed the mRNA expression of pro-inflammatory cytokines, such as Tnf-α, Il-1β, and Il-6. In addition, PCOs protected the intestinal barrier from damage by promoting the expression of mucins and tight junction proteins at both mRNA and protein levels. Upon 16S rDNA sequencing, it was observed that PCO treatment partly reversed the changes in the gut microbiota of colitis mice by selectively regulating the abundance of specific bacteria. And Odoribacter, Muribaculum, Desulfovibrio, Oscillibacter, Escherichia-Shigella, and Turicibacter might be the critical bacteria in improving colitis via PCOs. Finally, using antibiotic mixtures to destroy the intestinal bacteria, we documented that PCO fermentation broth (PCO FB) instead of PCOs prevented the occurrence of colitis in gut microbiota-depleted mice. In conclusion, PCOs showed a protective effect on colitis by reversing gut microbiota dysbiosis. Our study sheds light on the potential application of PCOs as a prebiotic for treating colitis.

Trypsin inhibitor LH011 inhibited DSS-induced mice colitis via alleviating inflammation and oxidative stress

Background: Ulcerative colitis (UC) is one type of inflammatory bowel disease, characterized by inflammation with infiltration and activation of macrophages in colonic tissue. LH011 is a trypsin inhibitor with potential anti-inflammatory effect.

Purpose: Here, we aim to assay the effects of LH011 on UC and further investigate the potential mechanisms in vitro and in vivo.

Methods: Dextran sulfate sodium (DSS, 3.5%, w/v) was used to induce UC, and lipopolysaccharide (LPS) was used to induce inflammation in RAW 264.7 cells. LH011 was administrated to mice in vivo or to RAW 264.7 cells in vitro at different concentrations. The cytokines (IL-1β, IL-6, and TNF-α) and the changes of NF-κB and Nrf2 pathways were detected.

Results: The results showed that LH011 improved DSS-induced mice colitis, including loss of weight, disease activity index (DAI), and colonic pathological damage. In addition, LH011 inhibited the expressions of IL-1β, IL-6, and TNF-α and strengthened the anti-oxidative capacity. Mechanically, LH011 downregulated the nuclear localization of NF-κB p65 and upregulated the protein expression of Nrf2.

Conclusion: These results demonstrated that LH011 alleviated inflammation and oxidative stress during UC by inhibiting TLR4/NF-κB and activating Nrf2/Keap1/HO-1 signaling pathways.

Evaluation of the cytotoxicity, oral toxicity, genotoxicity, and mutagenicity of the latex extracted from Himatanthus drasticus (Mart.) Plumel (Apocynaceae)

ETHNOPHARMACOLOGICAL RELEVANCE

Himatanthus drasticus is a tree popularly known as janaguba. Endemic to Brazil, it is found in the Cerrado and Caatinga biomes, rock fields, and rainforests. Janaguba latex has been used in folk medicine for its antineoplastic, anti-inflammatory, analgesic, and antiallergic activities. However, studies investigating the safety of its use for medicinal purposes are limited.

AIM OF THE STUDY

This study aimed to evaluate the toxicity of the latex extracted from H. drasticus.

MATERIALS AND METHODS

The latex was extracted from H. drasticus specimens by removing a small area of bark (5 × 30 cm) and then dissolving the exudate in water and lyophilizing it. Phytochemical screening was performed by TLC and GC-MS, protein, and carbohydrate levels. Cell viability was performed by the MTT method. Acute oral toxicity, genotoxicity, and mutagenicity assays were performed in mice.

RESULTS

TLC showed the presence of saponins and reducing sugars, as well as steroids and terpenes. The GC-MS analysis of the nonpolar fraction identified lupeol acetate, betulin, and α/β-amyrin derivatives as the major compounds. The latex was toxic to S-180 cells at 50 and 100 μg/mL. No signals of toxicity or mutagenicity was found in mice treated with 2000 mg/kg of the latex, but genotoxicity was observed in the Comet assay.

CONCLUSIONS

H. drasticus latex showed toxicity signals at high doses (2000 mg/kg). Although the latex was not mutagenic to mice, it was genotoxic in the Comet assay in our experimental conditions. Even testing a limit dose of 2000 mg/kg, which is between 10 to 35-fold the amount used in folk medicine, caution must be taken since there is no safe level for genotoxic compounds exposure. Further studies on the toxicological aspects of H. drasticus latex are necessary to elucidate its possible mechanisms of genotoxicity.

Anti-Inflammatory Mechanisms of Koreanaside A, a Lignan Isolated from the Flower of Forsythia koreana, against LPS-Induced Macrophage Activation and DSS-Induced Colitis Mice: The Crucial Role of AP-1, NF-κB, and JAK/STAT Signaling

The current treatment options for inflammatory bowel disease (IBD) are unsatisfactory. Therefore, novel and safer therapies are needed. We previously reported that koreanaside A (KA) showed high radical scavenging activity and suppressed vascular cell adhesion molecule 1 (VCAM-1) expression in vascular smooth muscle cells. However, the molecular mechanisms involved in its anti-inflammatory effect have not been reported. KA inhibited pro-inflammatory mediators such as inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), nitric oxide (NO), and prostaglandin E₂ (PGE₂). KA inhibited the production and mRNA expression of interleukin (IL)-6 and tumor necrosis factor-α (TNF-α) induced by LPS. KA downregulated the myeloid differentiation primary response 88 (MyD88)-dependent inflammatory gene expressions in the MyD88-overexpressed cells. KA suppressed the LPS-induced transcriptional and DNA-binding activities of activator protein-1 (AP-1) and nuclear factor-kappa B (NF-κB). KA was found to inhibit the phosphorylation of Janus kinase 1/2 (JAK1/2) and signal transducers and activators of transcription 1/3 (STAT1/3). In DSS-induced colitis mice, KA relieved the symptoms of colitis by suppressing inflammatory cell infiltration, restoring tight junction (TJ)- and epithelial–mesenchymal transition (EMT)-related protein expression, and inactivating AP-1, NF-κB, and STAT1/3. Therefore, KA reduced inflammatory responses by downregulating AP-1, NF-κB, and JAK/STAT signaling in LPS-induced macrophages and DSS-induced colitis mice.

Synthesis and suggestion of a new nanometric gold(III) melatonin drug complex: an interesting model for testicular protection

AIM

Melatonin (MLT) is a major hormone secreted by the pineal gland. In this study, a gold(III) MLT (Au⁺³/MLT) complex has been synthesized and investigating its protective effects against testicular damage.

METHODOLOGY

The structural features of the complex were investigated. For biological assessment, 30 male rats were divided into three groups for 30 days. The first control group, the second received MLT and the third received Au⁺³/MLT complex.

RESULTS

The Au⁺³/MLT complex was found to be nonelectrolytic with formula (Au[MLT]₂[Cl][H₂O]). The ligand is monodentate and adopt square-planar geometry. Its particles range in diameter from 35 to 100 nm. MLT affords slight oxidative stress protection. The Au⁺³/MLT complex significantly decreases TNF-α and IL-1β levels but elevates antioxidant enzyme capacities, reducing lipid peroxidation markers and improving testicular histological structure.

CONCLUSION

The Au⁺³/MLT complex improves the anti-inflammatory actions of MLT, exhibits potent antioxidant activity and enhances reproductive capacity.

Regulation of JAK2/STAT3 and NF-κB signal transduction pathways; Veronica polita alleviates dextran sulfate sodium-induced murine colitis

Ulcerative colitis (UC) is a major inflammatory bowel disease (IBD) has become a worldwide emergent disease. Veronica polita (VP) is a medicinal herb that has strong antioxidant and anti-inflammatory properties. In the present study, we studied the protective effect of VP on dextran sulfate sodium (DSS)-induced experimental colitis in mice. Phytochemical screening of VP extract demonstrated the presence of high total phenolic and flavonoid contents. Compared with the DSS group, VP significantly reduced clinical symptoms with less weight loss, bloody stool, shortening of the colon, and the severity of colitis was considerably inhibited as evidenced by the reduced disease activity index (DAI) and degree of histological damage in the colon and spleen. Also, treatment with VP considerably decreased the nitric oxide (NO) and malondialdehyde (MDA) level. VP remarkably downregulated the expression of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), inducible nitric oxide synthetase (iNOS) and cyclooxygenase-2 (COX-2) in the colon tissue. Likewise, activation of the signal transducer and activator of transcription 3 (STAT3) and nuclear factor-kappa B (NF-κB) was effectively blocked by VP. Taken together, these results demonstrate that VP has an ameliorative effect on colonic inflammation mediated by modulation of oxidative stress and inflammatory mediators by suppressing the JAK2/STAT3 and NF-κB signaling pathways.