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Abstract Nigella sativa (N. sativa) L. (Ranunculaceae), commonly referred to as black cumin, has a long history of usage as an herbal remedy. It has been utilized conventionally and in clinical settings to treat various illnesses. Six groups of male Wister rats were randomly selected as Gp I, represented as control; Gp II administered N. sativa aqueous extract (NSAE); 200 mg/kg/d, Gp III received N. sativa silver nanocomposite (NS-Ag-NC); 0.25 mg/kg/d; Gp IV administered thioacetamide (TAA);100 mg/kg; thrice weekly and Gps V and VI administered NSAE and NS-Ag-NC with TAA for six weeks, respectively. Findings showed that GC-MS analysis of NSAE has a high concentration of phytochemicals with strong antioxidant activity. Results revealed that TAA administration elevated TBARS, H2O2, PCC, NO levels, kidney function parameters, LDH activity, and up-regulated TNF-α, IL-1β, NF-kβ, and COX-2 gene expressions. In contrast, enzymatic and non-enzymatic antioxidants and ALP activity were extensively diminished. Also, severe abnormalities in lipid profile, hematological parameters, and histopathological features were noted. On the other hand, the administration of NSAE or NS-Ag-NC followed by TAA intoxication reduces renal impairment, restores the antioxidant system, and downregulates the expression of TNF-α, IL-1β, NF-kβ, and COX-2 genes in rats’ renal tissues. Collectively, NS-Ag-NC has more prevalent nephroprotective impacts than NSAE and can adjust the oxidant/antioxidant pathways besides their anti-inflammatory efficacy against TAA toxicity.

Abstract Background The TCF7L2 gene is a significant genetic factor contributing to the risk of metabolic and cardiovascular diseases (CVD). We previously found that subjects with the TT genotype of TCF7L2 rs7903146 variant, who consume a low-fat diet (LF) had a higher incidence of stroke than subjects with the CC genotype. Yet this association was abolished in subjects with the TT genotype who consumed a Mediterranean-type diet (MetD). However, the mechanism by which MetD diet modulates the association between TCF7L2 and CVD risk is unclear. This study aims to validate these findings under real-world conditions and clinical practice to elucidate the biological mechanisms involved in this correlation. Methods Thirty-five participants with BMI ranging from 27 to 34 kg/m2 were recruited based on rs7903146 genotype. Of those consented to participate, 21 had the CC and 14 had the TT genotype. Participants were randomly assigned to two dietary intervention groups, ensuring an equal distribution of CC and TT carriers. Each participant followed one of two diets (LF or MetD) for one week, followed by a 10-day washout period before switching to the other diet for one week. Blood samples were collected before and after each diet for metabolomic analysis using nuclear magnetic resonance (NMR) spectroscopy. The differential effect of the diets on triglyceride-rich lipoproteins was determined based on TCF7L2 genotype. Results The MetD significantly reduced triglyceride-rich lipoprotein concentrations compared to the LF diet. After consuming the LF diet, TT carriers exhibited more small VLDL particles, potentially contributing to CVD risk compared to CC carriers. However, this difference in risk was not observed with the MetD. Furthermore, the order in which the two diets were crossed affected the triglyceride-rich lipoprotein profile, with LF-MetD regimen showing a stronger effect on triglyceride-rich lipoproteins (TRL) levels than the MetD-LF regimen. Conclusions Our findings suggest that rs7903146 TT carriers benefit more from a MetD than a LF diet in terms of their triglyceride-rich lipoprotein profile, which may reduce their risk of CVD. These results support the notion that genotype is a factor in determining the extent to which the MetD affects cardiovascular health.

Abstract Background One-carbon metabolism links folate and methionine metabolism and this is essential for nucleotide synthesis in the cells. Alterations in one-carbon metabolism are associated with cardiovascular disease (CVD), type 2 diabetes and cancer. Our aim was to investigate whether SNPs in antioxidant-enzyme genes impact the concentrations of folate in serum (s-folate), plasma total homocysteine (p-tHcy) and total glutathione in plasma (p-tGSH) in healthy subjects after supplementation with folic acid. Methods In a randomized, double blind, crossover study, healthy subjects received 0.8 mg folic acid per day or a placebo for two weeks. Twenty-four male, and sixty-seven female subjects participated in this study. Participants were aged 36.4 ± 14.8 years (mean ± SD). We studied SNPs in six genes by PCR methods. The concentrations of s-folate, p-tHcy and p-tGSH were measured in fasting samples with Cobas and an HPLC-fluorescence method. Student T-tests and ANOVA were used for the statistical calculations. Main findings The subjects with SNP (rs4880) in superoxide dismutase (SOD2) gene (CC) allele had higher concentrations of s-folate and lower concentrations of p-tHcy than subjects with (CT + TT) alleles, (p = 0.014 and p = 0.012). Contrary to SOD2 (CC) allele, the subjects with SNP (rs1001179) catalase (CAT) CC allele had lower concentrations of s-folate (p = 0.029), higher concentrations of p-tGSH (0.017) and higher concentrations of p-tHcy before and after folic acid supplementations (p = 0.015, p = 0.017) than the subjects with (CT + TT) allele. Glutathione transferase (theta)1 (GST-T1) genotype was associated with higher concentrations of s-folate than GST-T0 before (p = 0.025) and after folic acid supplementation (p = 0.047). SNP (rs1050450) in glutathione peroxidase (GPX1) had also impact on the concentrations of p-tGSH (p = 0.011) in healthy subjects. Conclusion SNPs in SOD2 (rs4880), CAT (rs1001179), and GST1 impact the concentrations of s-folate, and p-tHcy in healthy subjects before and after folic acid supplementation. Our findings suggest that SNPs in antioxidant-genes have a role in health and disease by impacting the concentrations of s-folate, p-tHcy and p-tGSH.

Abstract Background Both zinc transporter 8 (ZnT8) and somatostatin (Sst) play crucial roles in the regulation of insulin and glucagon secretion. However, the interaction between them in controlling glucose metabolism was not well understood. The aim of this study was to explore the interactive effects of a double knockout of Znt8 and Sst on insulin and glucose metabolism in mice. Methods Co-expression of ZnT8 with hormones secreted from gastrointestinal endocrine cells of mice was determined using immunofluorescence. Male Znt8 knockout (Znt8KO), Sst knockout (SstKO), double knockout for Sst and Znt8 (DKO), and the wild-type (WT) mice were fed a regular chow diet (CD) or a high-fat diet (HFD) at 3 weeks old for 15 weeks. Weights and fasting or fed glucose levels were determined. Glucose and insulin tolerance tests were performed; metabolic-relevant hormone levels including insulin, glucagon, glucagon-like peptide 1, Pyy, and leptin were determined. Results ZnT8 is co-expressed with Sst in a subpopulation of endocrine D cells in the gastrointestinal tract. The absence of ZnT8 expression resulted in an increased density of the dense cores in the secretory granules of the D cell. DKO mice had reduced weight compared to WT when maintained on the CD. Compared to Znt8KO and SstKO, DKO mice did not show significant differences in fed or fasting blood glucose level regardless of dietary conditions. However, the CD-fed DKO mice had impaired insulin secretion without alterations in islet morphology or numbers. Moreover, DKO mice displayed diet-induced insulin resistance and disrupted secretion of metabolic-related hormones. Conclusions Somatostatin as well as a normal insulin sensitivity are required for normalizing glucose metabolism in Znt8KO mice. ZnT8 may play a role in regulating fat mass and leptin secretion. These findings shed light on the multifaceted nature of Znt8 and Sst interactions, opening new avenues to understand their roles in controlling glucose metabolism and fat mass.

This study aimed to evaluate soy isoflavones' effect and potential use—specifically genistein—in treating human keloid fibroblast cells (KFs) and in a keloid tissue culture model. To investigate the effects of genistein on keloid, a wound-healing assay was performed to detect cell migration. Flow cytometry was used to measure apoptosis. Western blotting and immunofluorescence staining were performed to detect the expression of target proteins. KF tissues were isolated, cultured, and divided into the control, silenced connective tissue growth factor (CTGF) proteins, and shNC (negative control) groups. Genistein suppressed cell proliferation and migration, triggering the cell cycle at the G2/M phase and increasing the expression of p53 dose-dependent in keloids. Genistein inhibited the expression of COL1A1, FN, and CTGF mRNA and protein. Knockdown CTGF reduced the migrated ability in KFs. Genistein also abated TGF-β1-induced keloid fibrosis through the endocytosis model. Separated and cultured the keloid patient’s tissues decreased the cell migration ability by genistein treatment and was time-dose dependent. This study indicated that genistein-induced p53 undergoes cell cycle arrest via the CTGF pathway-inhibited keloid cultured cells, and genistein suppressed the primary keloid cell migration, suggesting that our research provides a new strategy for developing drugs for treating keloids. 1. Genistein decreased proliferation and promoted cell cycle arrest at the G2/M phase in keloid cells. 2. Genistein inhibited the expression of COL1A1, FN, and CTGF mRNA and protein expressions. 3. Genistein enhanced endocytosis in keloids and blocked the stimulation of growth factor. 4. Genistein has therapeutic effects in treating keloids and preventing recurrence.

Quercetin is a promising phytochemical in treating abnormalities associated with metabolic syndrome (MetS). This study aimed to explore the morphometric, metabolic, transcriptomic, and nutrigenetic responses to quercetin supplementation using two genetically distinct MetS models that only differ in the variant of the MetS-related Zbtb16 gene (Zinc Finger And BTB Domain Containing 16). Quercetin supplementation led to a significant reduction in the relative weight of retroperitoneal adipose tissue in both investigated strains. A decrease in visceral (epididymal) fat mass, accompanied by an increase in brown fat mass after quercetin treatment, was observed exclusively in the SHR strain. While the levels of serum triglycerides decreased within both strains, the free fatty acids levels decreased in SHR-Zbtb16-Q rats only. The total serum cholesterol levels were not affected by quercetin in either of the two tested strains. While there were no significant changes in brown adipose tissue transcriptome, quercetin supplementation led to a pronounced gene expression shift in white retroperitoneal adipose tissue, particularly in SHR-Zbtb16-Q. Quercetin administration ameliorates certain MetS-related features; however, the efficacy of the treatment exhibits subtle variations depending on the specific variant of the Zbtb16 gene.

Lactic acid bacteria (LAB) probiotics are health-promoting but their characteristics, safety profile and functional mechanisms are not fully understood. Hence, this study aimed to characterize some hypothetical proteins of the chicken-isolated Limosilactobacillus reuteri genome and unravel their IL-2 and IL-10-inducing potential to understand mechanisms of their immunological functionality for sustainable applications. The selected proteins were subjected to in silico analyses for transmembrane topology, sub-cellular localization, IL-2 and IL-10-inducing ability and IL-2 and IL-10 gene expression across various conditions. IL-2 and IL-10-inducing mutants were statistically analyzed using a one-way analysis of variance of a general linear model of SAS and statistical significance was set at p < 0.05. The analyzed proteins are stable under a wide temperature range. All the hypothetical proteins are IL-2 and IL-10-inducing but QHPv.2.12, QHPv.2.13 and QHPv.2.15 are non-immunogenic. The evaluated mutants are IL-2 and IL-10-inducers but QHPv.2.13 and QHPv.2.15 are not immunogenic. This study sheds light on understanding the functional mechanisms of chicken-isolated L. reuteri and suggests it or its proteins as potent candidates for feed additive and therapeutic purposes.

AbstractRheumatoid arthritis (RA) is a chronic inflammatory autoimmune disorder. The present study aimed to evaluate the in silico, in vitro, and in vivo inhibitory effect of visnagin on malate dehydrogenase activity and elucidate its inflammatory efficacy when combined with methotrexate in the RA rat model. The molecular docking, ADMET simulations, MDH activity, expression, and X-ray imaging were detected. Moreover, CRP, RF, (anti-CCP) antibody, (TNF-α), (IL-6), (IL-17), and (IL-10) were evaluated. The expression levels of MMP3 and FOXP3 genes and CD4, CD25, and CD127 protein levels were assessed. Histological assessment of ankle joints was evaluated. The results revealed that visnagin showed reversible competitive inhibition on MDH with inhibitory constant (Ki) equal to 141 mM with theoretical IC50 equal to 1202.7 mM, LD50 equal to 155.39 mg/kg, and LD25 equal to 77.69 mg/kg. In vivo studies indicated that visnagin exhibited anti-inflammatory effects through decreasing MDH1 activity and expression and induced proliferation of anti-inflammatory CD4+CD25+FOXP3 regulatory T cells with increasing the anti-inflammatory cytokine IL-10 levels. Moreover, visnagin reduced the levels of inflammatory cytokines and the immuno-markers. Our findings elucidate that visnagin exhibits an anti-inflammatory impact against RA through its ability to inhibit the MDH1 enzyme, improve methotrexate efficacy, and reduce oxidative stress. Graphical Abstract

In a previous study, the 84-day administration of glycosaminoglycans (GAGs), with or without native collagen type II (NC), in an osteoarthritis (OA)-induced rabbit model slowed down OA progression, improved several micro- and macroscopic parameters and magnetic resonance imaging (MRI) biomarkers in cartilage, and increased hyaluronic acid levels in synovial fluid. To elucidate the potential underlying mechanisms, a transcriptomics approach was conducted using medial femoral condyle and trochlea samples. The administration of chondroitin sulfate (CS), glucosamine hydrochloride (GlHCl), and hyaluronic acid (HA), with (CGH-NC) or without (CGH) NC, strongly modulated several genes involved in chondrocyte extracellular matrix (ECM) remodeling and homeostasis when compared to non-treated rabbits (CTR group). Notably, both treatments shared the main mechanism of action, which was related to ECM modulation through the down-regulation of genes encoding proteolytic enzymes, such as ADAM metallopeptidase with thrombospondin type 1 motif, 9 (Adamts9), and the overexpression of genes with a relevant role in the synthesis of ECM components, such as aggrecan (Acan) in both CGH-NC and CGH groups, and fibronectin 1 (Fn1) and collagen type II, alpha 1 (Col2A1) in the CGH group. Furthermore, there was a significant modulation at the gene expression level of the mTOR signaling pathway, which is associated with the regulation of the synthesis of ECM proteolytic enzymes, only in CGH-NC-supplemented rabbits. This modulation could account for the better outcomes concerning the microscopic and macroscopic evaluations reported in these animals. In conclusion, the expression of key genes involved in chondrocyte ECM remodeling and homeostasis was significantly modulated in rabbits in response to both CGH and CGH-NC treatments, which would partly explain the mechanisms by which these therapies exert beneficial effects against OA.

This study aimed to identify markers of postprandial dysglycemia in the blood of self-described healthy individuals using dry blood spots (DBS) as a sampling strategy. A total of 54 volunteers, including 31 women, participated in a dietary challenge. They consumed a high-fat, high-sugar mixed meal and underwent multiple blood sampling over the course of 150 min to track their postprandial responses. Blood glucose levels were monitored with a portable glucometer and individuals were classified into two groups based on the glucose area under the curve (AUC): High-AUC (H-AUC) and Low-AUC (L-AUC). DBS sampling was performed at the same time points as the assessment of glycemia using Whatman 903 Protein Saver filter paper. A gas chromatography-mass spectrometry-based metabolite profiling was conducted in the DBS samples to assess postprandial changes in blood metabolome. Higher concentrations of metabolites associated with insulin resistance were observed in individuals from the H-AUC group, including sugars and sugar-derived products such as fructose and threonic acid, as well as organic acids and fatty acids such as succinate and stearic acid. Several metabolites detected in the GC-MS analysis remained unidentified, indicating that other markers of hyperglycemia remain to be discovered in DBS. Based on these observations, we demonstrated that the use of DBS as a non-invasive and inexpensive sampling tool allows the identification of metabolites markers of dysglycemia in the postprandial period.

Nonalcoholic fatty liver disease (NAFLD) is a prevalent chronic liver ailment that can lead to serious conditions such as cirrhosis and hepatocellular carcinoma. Hepatic Nogo-B regulates glucose and lipid metabolism, and its inhibition has been shown to be protective against metabolic syndrome. Increasing evidence suggests that imbalances in the gut microbiota (GM) and lipid metabolism disorders are significant contributors to NAFLD progression. Nevertheless, it is not yet known whether Nogo-B can affect NAFLD by influencing the gut microbiota and metabolites. Hence, the aim of the present study was to characterize this process and explore its possible underlying mechanisms. A NAFLD model was constructed by administering a high-fat diet (HFD) to Nogo-B−/− and WT mice from the same litter, and body weight was measured weekly in each group. The glucose tolerance test (GTT) and insulin tolerance test (ITT) were performed to assess blood glucose levels. At the end of the 12-week period, samples of serum, liver, and intestinal contents were collected and used for serum biochemical marker and inflammatory factor detection; pathology evaluation; and gut microbiome and metabolomics analysis. Spearman’s correlation analysis was performed to determine possible correlations between differential gut microbiota and differential serum metabolites between groups. Nogo-B deficiency attenuated the effects of the HFD, including weight gain, liver weight gain, impaired glucose tolerance, hepatic steatosis, elevated serum lipid biochemicals levels, and liver function. Nogo-B deficiency suppressed M1 polarization and promoted M2 polarization, thus inhibiting inflammatory responses. Furthermore, Nogo-B−/−-HFD-fed mice presented increased gut microbiota richness and diversity, decreased Firmicutes/Bacteroidota (F/B) ratios, and altered serum metabolites compared with those of WT-HFD-fed mice. During analysis, several differential gut microbiota, including Lachnoclostridium, Harryflintia, Odoribacter, UCG-009, and unclassified_f_Butyricoccaceae, were screened between groups. These microbiota were found to be positively correlated with upregulated purine metabolism and bile acid metabolites in Nogo-B deficiency, while they were negatively correlated with downregulated corticosterone and tricarboxylic acid cyclic metabolites in Nogo-B deficiency. Nogo-B deficiency delayed NAFLD progression, as demonstrated by reduced hepatocellular lipid accumulation, attenuated inflammation and liver injury, and ameliorated gut microbiota dysbiosis and metabolic disorders. Importantly, Odoribacter was strongly positively correlated with ALB and taurodeoxycholic acid, suggesting that it played a considerable role in the influence of Nogo-B on the progression of NAFLD, a specific feature of NAFLD in Nogo-B−/− mice. The regulation of bile acid metabolism by the gut microbiota may be a potential target for Nogo-B deficiency to ameliorate NAFLD.