Chronic Dexamethasone exposure activates the TLR4-Mediated inflammation pathway and induces epithelial apoptosis in the goat colon

Flavonoids of Euphorbia hirta inhibit inflammatory mechanisms via Nrf2 and NF-κB pathways

Euphorbia hirta has anti-inflammatory effects in traditional medicine, but its anti-inflammatory mechanism has not been explored at the cellular and molecular levels. To unravel these mechanisms, the main active components in the 65 and 95% ethanol extracts of Euphorbia hirta were first identified by UPLC-Q-TOF/MS. Subsequently, potential anti-inflammatory targets and signaling pathways were predicted using network pharmacology and experimentally validated using RT-PCR and flow cytometry in a lipopolysaccharide (LPS)-induced inflammation model of RAW264.7 cells. The results revealed flavonoids as the key active components. Network pharmacology uncovered 71 potential anti-inflammation targets, with a protein-protein interaction (PPI) network highlighting 8 cores targets, including IL-6, TNF, NFκB and Nrf2 et al. Furthermore, Euphorbia hirta exerts anti-inflammation effects through modulation of Nrf2 and NF-κB signaling pathways. Specifically, the 65% ethanol extract of Euphorbia hirta (EE65) and quercitrin (HPG) exerted anti-inflammatory activity by inhibiting the expression of inflammatory genes associated with the NF-κB signaling pathway, whereas baicalein (HCS) suppressed cellular inflammation by promoting Nrf2-mediated antioxidant gene expression and enhancing apoptosis of inflammatory cells. The results of the study suggest that Euphorbia hirta has potential for the development of anti-inflammatory drugs.

Chronic Dexamethasone Disturbs the Circadian Rhythm of Melatonin and Clock Genes in Goats

Dex is a drug commonly used as an immunosuppressive and anti-inflammatory agent in humans and animals. GCs have a profound impact on melatonin expression and biological rhythm. However, the effect of chronic exposure to Dex on melatonin secretion and biological clock gene expression in ruminants is still unclear. Ten goats were randomly divided into two groups: the control group was injected with saline, and the Dex-treated group was intramuscularly injected daily for 21 d with 0.2 mg/kg Dex. The rhythm of melatonin secretion in the plasma was disturbed in the Dex group, and the plasma and colon levels of melatonin were lower in the Dex group compared to the control group (p < 0.05). Dex leads to a significant decrease in the expression of Arylalkylamine N-acetyltransferase (AANAT), a key melatonin synthase, in the pineal gland and colon. Detecting intestinal leakage-related indices showed that diamine oxidase (DAO) and lipopolysaccharide (LPS) content increased significantly in the Dex group (p < 0.05). We also detected genes associated with biological rhythms in the plasma. In the control group, the five tested genes showed circadian rhythms, but the circadian rhythms of Clock, Cry1, Cry2, and Per2 were abolished or blunted by the Dex (p < 0.05). Protein levels of CLOCK and BMAL1 in the colon changed significantly (p < 0.05). In conclusion, the above experimental results show that chronic exposure to Dex leads to the disorder of the circadian rhythms of melatonin secretion and clock genes.

Protective potential of Bacillus subtilis (NMCC-path-14) against extraarticular manifestations during acute and sub-acute phase of arthritis using mice model

Extra-articular manifestations (EAM), which are associated with rheumatoid arthritis (RA), affect the quality of life of patients and are one of the critical causes of early mortality. This study was aimed at investigating whether Bacillus subtilis NMCC-path-14 (1 × 108 CFU/animal/day) could serve as a valuable therapeutic agent in managing EAM using complete Freund's adjuvant (CFA) induced arthritis during acute and sub-acute phases. Arthritis was induced using intra-dermal administration of CFA in the right hind paw of mice on day 1. Dexamethasone (Dexa) (5 mg/kg/day/animal) was used as a standard treatment. Animals in Dexa and Bacillus subtilis concurrent treatment (BS-CT) received treatments on day 1. The Bacillus subtilis pre-treatment (BS-PT) group received a probiotic dose 7 days before arthritis induction. Parameters like body weight, relative organ weight, colon length, hematology, serum biochemistry, antioxidant capacity, and histopathology of liver, kidney, spleen, colon, stress-related behavioral changes, and cortisol levels were evaluated on days 7 (acute) and 14 (sub-acute). Dexa failed to manage the EAM in arthritic mice and instead exacerbated them. On the other hand, B. subtilis NMCC-path-14 significantly declined EAM with no notable side effects, highlighting its safety and effectiveness. The current data show that B. subtilis NMCC-path-14 may be an alternative option for arthritis treatment that can reduce systemic symptoms associated with arthritis. More studies are required to comprehend the underlying mechanisms of mitigating the EAM by B. subtilis NMCC-path-14.

Effects of cortisone in zebrafish (Danio rerio): Insights into gut microbiota interactions and molecular mechanisms underlying DNA damage and apoptosis

Cortisone can enter aquatic ecosystems and pose a risk to organisms therein. However, few studies have explored the effects of cortisone on the gut microbiota of aquatic organisms. Here, we exposed zebrafish (Danio rerio) to cortisone at environmentally relevant concentrations (5.0, 50.0, or 500.0 ng L-1) for 60 days to explore its toxicological effects and their association with gut microbiota changes. The terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling assay revealed that exposure to 50 ng L-1 cortisone significantly increased the intestinal cell apoptosis rate, 8-hydroxydeoxyguanosine contents, and caspase-3 and caspase-8 activities. Moreover, the transcriptome analysis results demonstrated a notable downregulation in the expression of most differentially expressed genes associated with apoptosis pathways, as well as changes in DNA replication, oxidative stress, and drug metabolism pathways; these results indicated the occurrence of cortisone-induced stress response in zebrafish. Molecular docking analysis revealed that cortisone can bind to caspase-3 through hydrogen bonds and hydrophobic interactions but that no such interactions occur between cortisone and caspase-8. Thus, cortisone may induce oxidative DNA damage and apoptosis by activating caspase-3. Finally, the 16S rRNA sequencing results demonstrated that cortisone significantly affected microbial community structures and functions in the intestinal ecosystem. These changes may indicate gut microbiota response to cortisone-induced intestinal damage and inflammation. In conclusion, the current results clarify the mechanisms underlying intestinal response to cortisone exposure and provide a basis for evaluating the health risks of cortisone in animals.

Synthesis and Anti-Cancer Activity of the Novel Selective Glucocorticoid Receptor Agonists of the Phenylethanolamine Series

Glucocorticoids (GCs) are widely used for treating hematological malignancies despite their multiple adverse effects. The biological response to GCs relies on glucocorticoid receptor (GR) transrepression (TR) that mediates the anticancer effects and transactivation (TA) associated with the side effects. Selective GR agonists (SEGRAs) preferentially activating GR TR could offer greater benefits in cancer treatment. One of the well-characterized SEGRAs, 2-(4-acetoxyphenyl)-2-chloro-N-methylethylammonium-chloride (CpdA), exhibited anticancer activity; however, its translational potential is limited due to chemical instability. To overcome this limitation, we obtained CpdA derivatives, CpdA-01-CpdA-08, employing two synthetic strategies and studied their anti-tumor activity: 4-(1-hydroxy-2-(piperidin-1-yl)ethyl)phenol or CpdA-03 demonstrated superior GR affinity and stability compared to CpdA. In lymphoma Granta and leukemia CEM cell lines, CpdA-03 ligand exhibited typical SEGRA properties, inducing GR TR without triggering GR TA. CpdA-03 effects on cell viability, growth, and apoptosis were similar to the reference GR ligand, dexamethasone (Dex), and the source compound CpdA. In vivo testing of CpdA-03 activity against lymphoma on the transplantable P388 murine lymphoma model showed that CpdA-03 reduced tumor volume threefold, outperforming Dex and CpdA. In conclusion, in this work, we introduce a novel SEGRA CpdA-03 as a promising agent for lymphoma treatment with fewer side effects.

Imatinib prevents dexamethasone-induced pancreatic β-cell apoptosis via decreased TRAIL and DR5

Prolonged administration of dexamethasone, a potent anti-inflammatory drug, can lead to steroid-induced diabetes. Imatinib, a medication commonly prescribed for chronic myeloid leukemia (CML), has been shown to improve diabetes in CML patients. Our recent study demonstrated that dexamethasone induces pancreatic β-cell apoptosis by upregulating the expression of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and its receptor, death receptor 5 (DR5). We hypothesized that imatinib may protect against dexamethasone-induced pancreatic β-cell apoptosis by reducing the expression of TRAIL and DR5, thereby favorably modulating downstream effectors in apoptotic pathways. We test this hypothesis by assessing the effects of imatinib on dexamethasone-induced apoptosis in rat insulinoma cell line cells. As anticipated, dexamethasone treatment led to increased TRAIL and DR5 expression, as well as an elevation in superoxide production. Conversely, expression of the TRAIL decoy receptor (DcR1) was decreased. Moreover, key effectors in the extrinsic and intrinsic apoptosis pathways, such as B-cell lymphoma 2 (BCL-2) associated X (BAX), nuclear factor kappa B (NF-κb), P73, caspase 8, and caspase 9, were upregulated, while the antiapoptotic protein BCL-2 was downregulated. Interestingly and importantly, imatinib at a concentration of 10 µM reversed the effect of dexamethasone on TRAIL, DR5, DcR1, superoxide production, BAX, BCL-2, NF-κB, P73, caspase 3, caspase 8, and caspase 9. Similar effects of imatinib on dexamethasone-induced TRAIL and DR5 expression were also observed in isolated mouse islets. Taken together, our findings suggest that imatinib protects against dexamethasone-induced pancreatic β-cell apoptosis by reducing TRAIL and DR5 expression and modulating downstream effectors in the extrinsic and intrinsic apoptosis pathways.

MODULATION OF INTESTINAL BARRIER FUNCTION BY GLUCOCORTICOIDS: LESSONS FROM PRECLINICAL MODELS

Glucocorticoids (GCs) are widely used drugs for their anti-inflammatory and immunosuppressant effects, but they are associated with multiple adverse effects. Despite their frequent oral administration, relatively little attention has been paid to the effects of GCs on intestinal barrier function. In this review, we present a summary of the published studies on this matter carried out in animal models and cultured cells. In cultured intestinal epithelial cells, GCs have variable effects in basal conditions and generally enhance barrier function in the presence of inflammatory cytokines such as tumor necrosis factor (TNF). In turn, in rodents and other animals, GCs have been shown to weaken barrier function, with increased permeability and lower production of IgA, which may account for some features observed in stress models. When given to animals with experimental colitis, barrier function may be debilitated or strengthened, despite a positive anti-inflammatory activity. In sepsis models, GCs have a barrier-enhancing effect. These effects are probably related to the inhibition of epithelial cell proliferation and wound healing, modulation of the microbiota and mucus production, and interference with the mucosal immune system. The available information on underlying mechanisms is described and discussed.

Impacts of Epigenetic Processes on the Health and Productivity of Livestock

The dynamic changes in the epigenome resulting from the intricate interactions of genetic and environmental factors play crucial roles in individual growth and development. Numerous studies in plants, rodents, and humans have provided evidence of the regulatory roles of epigenetic processes in health and disease. There is increasing pressure to increase livestock production in light of increasing food needs of an expanding human population and environment challenges, but there is limited related epigenetic data on livestock to complement genomic information and support advances in improvement breeding and health management. This review examines the recent discoveries on epigenetic processes due to DNA methylation, histone modification, and chromatin remodeling and their impacts on health and production traits in farm animals, including bovine, swine, sheep, goat, and poultry species. Most of the reports focused on epigenome profiling at the genome-wide or specific genic regions in response to developmental processes, environmental stressors, nutrition, and disease pathogens. The bulk of available data mainly characterized the epigenetic markers in tissues/organs or in relation to traits and detection of epigenetic regulatory mechanisms underlying livestock phenotype diversity. However, available data is inadequate to support gainful exploitation of epigenetic processes for improved animal health and productivity management. Increased research effort, which is vital to elucidate how epigenetic mechanisms affect the health and productivity of livestock, is currently limited due to several factors including lack of adequate analytical tools. In this review, we (1) summarize available evidence of the impacts of epigenetic processes on livestock production and health traits, (2) discuss the application of epigenetics data in livestock production, and (3) present gaps in livestock epigenetics research. Knowledge of the epigenetic factors influencing livestock health and productivity is vital for the management and improvement of livestock productivity.