Thymosin β4 Prevents Oxidative Stress, Inflammation, and Fibrosis in Ethanol- and LPS-Induced Liver Injury in Mice

Diosmin alleviates ulcerative colitis in mice by increasing Akkermansia muciniphila abundance, improving intestinal barrier function, and modulating the NF-κB and Nrf2 pathways

Ulcerative colitis is a common type of inflammatory bowel disease that affects millions of individuals around the world. Traditional UC treatment has focused on suppressing immune responses rather than treating the underlying causes of UC, which include oxidative stress, inflammation, and microbiota dysbiosis. Diosmin (DIO), a naturally occurring flavonoid, possesses antioxidant and anti-inflammatory properties. This study aimed to assess the efficacy of DIO in treating dextran-sulfate sodium (DSS)-induced colitis, and to investigate some of its underlying mechanisms, with an emphasis on Akkermansia muciniphila abundance, inflammatory markers, and intestinal barrier function. C57BL/6 mice were given 4% (w/v) DSS to induce colitis. DSS-induced mice were administered DIO (100 and 200 mg/kg) or sulfasalazine orally for 7 days. Every day, the disease activity index (DAI) was determined by recording body weight, diarrhea, and bloody stool. Changes in fecal A. muciniphila abundance, colonic MUC1 and MUC2 expression, as well as oxidative stress and inflammatory markers were all assessed. Histopathological changes, colonic PIK3PR3 and ZO-1 levels, and immunohistochemical examinations of occludin and claudin-1, were investigated. DIO administration resulted in a dose-dependent decrease in DAI, as well as increase in A. muciniphila abundance and MUC2 expression while decreasing MUC1 expression. DIO also dramatically reduced colonic oxidative stress and inflammation by regulating the NF-κB and Nrf2 cascades, restored intestinal barrier integrity by inhibiting PIK3R3 and inducing ZO-1, and improved occludin/claudin-1 gene expression and immunostaining. This study provides the first evidence that DIO preserves intestinal barrier integrity and increases A. muciniphila abundance in DSS-induced colitis. However, more research is required to explore the impact of DIO on the overall composition and diversity of the gut microbiota. Likewise, it will be important to fully understand the molecular mechanisms by which A. muciniphila maintains intestinal barrier function and its potential use as an adjuvant in the treatment of UC.

Designing Composite Stimuli-Responsive Hydrogels for Wound Healing Applications: The State-of-the-Art and Recent Discoveries

Effective wound treatment has become one of the most important challenges for healthcare as it continues to be one of the leading causes of death worldwide. Therefore, wound care technologies significantly evolved in order to provide a holistic approach based on various designs of functional wound dressings. Among them, hydrogels have been widely used for wound treatment due to their biocompatibility and similarity to the extracellular matrix. The hydrogel formula offers the control of an optimal wound moisture level due to its ability to absorb excess fluid from the wound or release moisture as needed. Additionally, hydrogels can be successfully integrated with a plethora of biologically active components (e.g., nanoparticles, pharmaceuticals, natural extracts, peptides), thus enhancing the performance of resulting composite hydrogels in wound healing applications. In this review, the-state-of-the-art discoveries related to stimuli-responsive hydrogel-based dressings have been summarized, taking into account their antimicrobial, anti-inflammatory, antioxidant, and hemostatic properties, as well as other effects (e.g., re-epithelialization, vascularization, and restoration of the tissue) resulting from their use.

Upregulated Tβ4 expression in inflammatory bowel disease impairs the intestinal mucus barrier by inhibiting autophagy in mice

Disrupted intestinal barrier homeostasis is fundamental to inflammatory bowel disease. Thymosin β4 (Tβ4) improves inflammation and has beneficial effects in dry-eye diseases, but its effects on the intestinal mucus barrier remain unknown. Therefore, this study evaluated the underlying regulatory mechanisms and effects of Tβ4 by examining Tβ4 expression in a mouse model with dextran sodium sulfate (DSS)-induced colitis and colonic barrier damage. Additionally, we intraperitoneally injected C57BL/6 mice with Tβ4 to assess barrier function, microtubule-associated protein 1 light chain 3 (LC3II) protein expression, and autophagy. Finally, normal human colon tissue and colon carcinoma cells (Caco2) were cultured to verify Tβ4-induced barrier function and autophagy changes. Mucin2 levels decreased, microbial infiltration increased, and Tβ4 expression increased in the colitis mouse model versus the control mice, indicating mucus barrier damage. Moreover, Tβ4-treated C57BL/6 mice had damaged intestinal mucus barriers and decreased LC3II levels. Tβ4 also inhibited colonic mucin2 production, disrupted tight junctions, and downregulated autophagy; these results were confirmed in Caco2 cells and normal human colon tissue. In summary, Tβ4 may be implicated in colitis by compromising the integrity of the intestinal mucus barrier and inhibiting autophagy. Thus, Tβ4 could be a new diagnostic marker for intestinal barrier defects.

Effect of thymosin β4 on lipopolysaccharide‑stimulated brain microvascular endothelial cell remodeling: A possible role in blood‑brain barrier injury

War veterans, in particular, are more prone to mental illness as they are more likely to have encountered multiple traumatic brain injuries (TBIs) whilst serving on active duty in war zone areas. A TBI is known to cause mortality or serious neurological disabilities among survivors and elicits a number of pathological processes, including neuroinflammation and blood brain barrier (BBB) disruption, leading to secondary brain damage and subsequent impairment of the neurovascular unit. Although several drugs exhibit promising effects for TBI, the repertoire of currently available therapeutic strategies remains limited. Thymosin 4 (Tβ4) is a 43-amino acid G-acting sequestering peptide that confers neuroprotective potential in TBI models. However, its role in BBB function remains unclear. Further research into the mechanism of BBB disruption induced by TBI and its specific role in neurovascular pathophysiology is necessary. In the present study, the protective effects of Tβ4 in lipopolysaccharide (LPS)-stimulated gene expression of several tight junction proteins, inflammatory genes, apoptotic genes, and adhesion genes in human brain microvascular endothelial cells (hBMVECs), one of the pivotal cell types in the BBB, were reported. The results suggested that pretreatment with Tβ4 reversed the LPS-induced damage of BBB components in hBMVECs. Furthermore, these results identified neuregulin 1 as a possible target for Tβ4. Therefore, it is proposed that Tβ4-mediated cellular signaling in hBMVEC may be vital for understanding the association between the BBB and TBI pathophysiology, which warrants further investigation.

Deficiency of endothelial sirtuin1 in mice stimulates skeletal muscle insulin sensitivity by modifying the secretome

Downregulation of endothelial Sirtuin1 (Sirt1) in insulin resistant states contributes to vascular dysfunction. Furthermore, Sirt1 deficiency in skeletal myocytes promotes insulin resistance. Here, we show that deletion of endothelial Sirt1, while impairing endothelial function, paradoxically improves skeletal muscle insulin sensitivity. Compared to wild-type mice, male mice lacking endothelial Sirt1 (E-Sirt1-KO) preferentially utilize glucose over fat, and have higher insulin sensitivity, glucose uptake, and Akt signaling in fast-twitch skeletal muscle. Enhanced insulin sensitivity of E-Sirt1-KO mice is transferrable to wild-type mice via the systemic circulation. Endothelial Sirt1 deficiency, by inhibiting autophagy and activating nuclear factor-kappa B signaling, augments expression and secretion of thymosin beta-4 (Tβ4) that promotes insulin signaling in skeletal myotubes. Thus, unlike in skeletal myocytes, Sirt1 deficiency in the endothelium promotes glucose homeostasis by stimulating skeletal muscle insulin sensitivity through a blood-borne mechanism, and augmented secretion of Tβ4 by Sirt1-deficient endothelial cells boosts insulin signaling in skeletal muscle cells.

The Protective Effect of Broccoli Seed Extract against Lipopolysaccharide-Induced Acute Liver Injury via Gut Microbiota Modulation and Sulforaphane Production in Mice

Broccoli seed extract (BSE) is rich in glucoraphanin (GRP), which may be transformed by intestinal microbes into sulforaphane (SFN), a compound with strong anti-inflammatory and antioxidant activities. Liver injury usually presents with inflammation and oxidative damage. Thus, dietary BSE supplementation may be an effective approach for alleviating liver injury. In this study, a mouse lipopolysaccharide (LPS)-induced acute liver injury model was used to evaluate the preventive effect of BSE and explore the relevant mechanisms. Compared with the LPS model group, the mice in the BSE group showed significantly lower activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), and lactate dehydrogenase (LDH) and higher levels of catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activity. Meanwhile, BSE significantly reduced the levels of pro-inflammatory cytokines (including IL-6 and TNF-α) in the liver and increased the level of anti-inflammatory factor (IL-10), indicating that BSE had a good preventive effect on acute liver injury. Additionally, after BSE intervention, the diversity of intestinal microbiota in the mice was higher than that in the LPS model group. The relative abundance of Akkermansia and Lactobacillus increased, while the relative abundance of Xylanophilum decreased. A correlation analysis revealed that the activities of SOD, GSH-Px, CAT and levels of IL-10 were positively correlated with the relative abundance of Lactobacillus. Furthermore, sulforaphane (SFN) and (Sulforaphane-N-Acetyl-Cysteine) SFN-NAC were detected in the urine of the mice after BSE intervention. Both q-PCR and an immunohistochemical analysis showed that BSE significantly regulated the expression level of the NF-κB (IκB-α, NF-κB) and Nrf2 (Nrf2, p-Nrf2 and HO-1) signaling pathways in the liver. In conclusion, BSE was shown to reduce LPS-induced acute liver injury through the conversion of glucoraphanin into sulforaphane and the regulation of the gut microbiota composition. These results suggest that BSE could be a promising ingredient in functional foods.

Thymosin β4 exerts cytoprotective function and attenuates liver injury in murine hepatic sinusoidal obstruction syndrome after hematopoietic stem cell transplantation

Hepatic sinusoidal obstruction syndrome (HSOS) is one of the life-threatening complications that may occur after hematopoietic stem cell transplantation (HSCT). Hepatic sinusoidal endothelial cells (HSECs) injury and liver fibrosis are key mechanisms of HSOS. Thymosin β4 (Tβ4) is an active polypeptide that functions in a variety of pathological and physiological states such as inflammation regulation, anti-apoptosis and anti-fibrosis. In this study, we found that Tβ4 can stimulate HSECs proliferation, migration and tube formation in vitro via activation of pro-survival signaling AKT (protein kinase B). In addition, Tβ4 resisted γ irradiation-induced HSECs growth arrest and apoptosis in parallel with upregulation of anti-apoptotic protein B-cell lymphoma-extra-large (Bcl-xL) and B-cell lymphoma-2 (Bcl-2), which may be associated with activation of AKT. More importantly, Tβ4 significantly inhibited irradiation-induced proinflammatory cytokines in parallel with negative regulation of TLR4/MyD88/NF-κB and MAPK p38. Meanwhile, Tβ4 reduced intracellular reactive oxygen species production and upregulated antioxidants in HSECs. Additionally, Tβ4 inhibited irradiation-induced activation of hepatic stellate cells via downregulation expression of fibrogenic markers α-SMA, PAI-1 and TGF-β. In a murine HSOS model, levels of circulating alanine aminotransferase, aspartate aminotransferase, total bilirubin, and pro-inflammatory cytokines IL-6, IL-1β and TNF-α were significantly reduced after administration of Tβ4 peptide; further, Tβ4 treatment successfully ameliorated HSECs injury, inflammatory damage and fibrosis of murine liver. Taken together, Tβ4 stimulates proliferation and angiogenesis of HSECs, exerts cytoprotective effect and attenuates liver injury in murine HSOS model, which could be a potential strategy to prevent and treat HSOS after HSCT.

Mucosal-associated invariant T cells restrict reactive oxidative damage and preserve meningeal barrier integrity and cognitive function

Increasing evidence indicates close interaction between immune cells and the brain, revising the traditional view of the immune privilege of the brain. However, the specific mechanisms by which immune cells promote normal neural function are not entirely understood. Mucosal-associated invariant T cells (MAIT cells) are a unique type of innate-like T cell with molecular and functional properties that remain to be better characterized. In the present study, we report that MAIT cells are present in the meninges and express high levels of antioxidant molecules. MAIT cell deficiency in mice results in the accumulation of reactive oxidative species in the meninges, leading to reduced expression of junctional protein and meningeal barrier leakage. The presence of MAIT cells restricts neuroinflammation in the brain and preserves learning and memory. Together, our work reveals a new functional role for MAIT cells in the meninges and suggests that meningeal immune cells can help maintain normal neural function by preserving meningeal barrier homeostasis and integrity.

The Role of Tβ4-POP-Ac-SDKP Axis in Organ Fibrosis

Fibrosis is a pathological process in which parenchymal cells are necrotic and excess extracellular matrix (ECM) is accumulated due to dysregulation of tissue injury repair. Thymosin β4 (Tβ4) is a 43 amino acid multifunctional polypeptide that is involved in wound healing. Prolyl oligopeptidase (POP) is the main enzyme that hydrolyzes Tβ4 to produce its derivative N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) which is found to play a role in the regulation of fibrosis. Accumulating evidence suggests that the Tβ4-POP-Ac-SDKP axis widely exists in various tissues and organs including the liver, kidney, heart, and lung, and participates in the process of fibrogenesis. Herein, we aim to elucidate the role of Tβ4-POP-Ac-SDKP axis in hepatic fibrosis, renal fibrosis, cardiac fibrosis, and pulmonary fibrosis, as well as the underlying mechanisms. Based on this, we attempted to provide novel therapeutic strategies for the regulation of tissue damage repair and anti-fibrosis therapy. The Tβ4-POP-Ac-SDKP axis exerts protective effects against organ fibrosis. It is promising that appropriate dosing regimens that rely on this axis could serve as a new therapeutic strategy for alleviating organ fibrosis in the early and late stages.

Hypermethylation of thymosin β4 predicts a poor prognosis for patients with acute-on-chronic hepatitis B liver failure

BACKGROUND

It has been demonstrated that thymosin β4 (Tβ4) could inflect the severity of acute-on-chronic hepatitis B liver failure (ACHBLF), but the relationship between its methylation status and the prognosis of liver failure is not clear. This study aimed to determine Tβ4 promoter methylation status in patients with ACHBLF and to evaluate its prognostic value.

METHODS

The study recruited 115 patients with ACHBLF, 80 with acute-on-chronic hepatitis B pre-liver failure (pre-ACHBLF), and 86 with chronic hepatitis B (CHB). In addition, there were 36 healthy controls (HCs) from the Department of Hepatology, Qilu Hospital of Shandong University. The 115 patients with ACHBLF were divided into three subgroups: 33 with early stage ACHBLF (E-ACHBLF), 42 with mid-stage ACHBLF (M-ACHBLF), and 40 with advanced stage ACHBLF (A-ACHBLF). Tβ4 promoter methylation status in peripheral blood mononuclear cells (PBMCs) was measured by methylation-specific polymerase chain reaction, and mRNA was detected by quantitative real-time polymerase chain reaction.

RESULTS

Methylation frequency of Tβ4 was significantly higher in patients with ACHBLF than in those with pre-ACHBLF, CHB or HC. However, expression of Tβ4 mRNA showed the opposite trend. In patients with ACHBLF, Tβ4 promoter methylation status correlated negatively with mRNA levels. The 3-month mortality of ACHBLF in the methylated group was significantly higher than that in the unmethylated group. Also, Tβ4 promoter methylation frequency was lower in survivors than in non-survivors. When used to predict the 1-, 2-, and 3-month incidence of ACHBLF, Tβ4 methylation status was better than the model for end-stage liver disease (MELD) score. The predictive value of Tβ4 methylation was higher than that of MELD score for the mortality of patients with E-ACHBLF and M-ACHBLF, but not for A-ACHBLF.

CONCLUSIONS

Tβ4 methylation might be an important early marker for predicting disease incidence and prognosis in patients with ACHBLF.

Thymosin β4 Protects against Cardiac Damage and Subsequent Cardiac Fibrosis in Mice with Myocardial Infarction

Background

Inflammation is a critical factor in the development and progression of myocardial infarction and cardiac fibrosis. Thymosin β4 (Tβ4) alleviates the disease process via protective antioxidant and anti-inflammatory mechanisms. Although Tβ4 has been shown to have a protective effect in myocardial infarction, its impact on cardiac fibrosis has not been well reported. In this study, we evaluated the influence of exogenous Tβ4 on myocardial infarction and cardiac fibrosis and explored the possible underlying mechanism.

Methods

Real-time quantitative reverse-transcription PCR (qRT-PCR), immunohistochemistry (IHC), and Western blot were used to analyze Tβ4 expression in acute myocardial infarction (AMI) cardiac tissues. The effects of intraperitoneal adeno-associated virus-Tβ4 (AAV-Tβ4) on ligation-induced AMI in mice were studied using cardiac function parameters, and RT-PCR, Western blot, HE staining, Masson staining, and IHC were used to assess the degree of myocardial fibrosis. The effects of Tβ4 were confirmed in vitro using mouse cardiac myocytes and myofibroblasts.

Results

Tβ4 was shown to be significantly elevated in mice AMI cardiac tissues. In mice, AAV-Tβ4 induced exogenous expression of Tβ4 significantly reduced oxidative damage, inflammation, cardiac dysfunction, and fibrosis. H₂O₂ inhibited mitophagy and increased inflammation in mouse cardiac myocytes via oxidative stress, and Tβ4 substantially reduced mitophagy inhibition and inflammasome activation in myocytes caused by H₂O₂. Furthermore, Tβ4 decreased cardiac myofibroblast growth and reduced TGF-β1-induced activation.

Conclusions

AAV-Tβ4 induced expression of Tβ4 reduced inflammation, heart damage, and eventual fibrosis in vivo. Tβ4 helped to reduce oxidative stress, promote mitophagy, and alleviate inflammation and fibrosis. Exogenous supplementation of Tβ4 might be a promising therapeutic agent for treating myocardial infarction as well as cardiac fibrosis.

Radix Puerariae thomsonii polysaccharide (RPP) improves inflammation and lipid peroxidation in alcohol and high-fat diet mice by regulating gut microbiota

Polysaccharides are the important active constituents of Radix Puerariae thomsonii. Numerous studies have shown that polysaccharides can regulate gut microbiota, repair intestinal barrier, and affect the microbiota-intestine-liver axis, thereby showing therapeutic effects on metabolic disorders. In this study, Radix Puerariae thomsonii polysaccharide (RPP) was extracted from Radix Puerariae thomsonii. The average Mw of RPP was determined to be 1.09 × 10⁵ Da and the monosaccharide composition showed it consisted of glucose. The effects and underlying mechanisms of RPP on fatty liver were studied using C57/BL6J mice induced by alcohol and high-fat diet. The results showed that the oral supplementation of RPP could alleviate alcohol and high-fat diet-induced hepatic injury and steatosis. RPP also promoted intestinal barrier integrity and reduced inflammation through NF-κB signaling pathway. RPP could ameliorate the lipid peroxidation by AMPK/NADPH oxidase signaling pathway. Additionally, these improvements might be related to the enrichment of intestinal bacteria Parabacteroides (promote intestinal barrier integrity) and Prevotellaceae UCG 001 (activation of AMPK signaling pathway). These results demonstrated that RPP could improve inflammation and lipid peroxidation in the alcohol and high-fat diet mouse by restoring the intestinal barrier integrity and regulating the gut microbiota. This suggested that RPP was a potential food supplement for the treatment of fatty liver disease.

Hypomethylation of thymosin β4 promoter is associated with glucocorticoid therapy in patients with acute-on-chronic hepatitis B-induced liver failure

BACKGROUND

We aimed to determine whether the methylation status of thymosin β4 (Tβ4) promoter reflects the severity of acute-on-chronic hepatitis B liver failure (ACHBLF) and whether glucocorticoids affect this status.

METHODS

Fifty-six patients with ACHBLF, 45 with chronic hepatitis B (CHB) and 32 healthy controls (HCs), were retrospectively enrolled. Methylation-specific PCR and real-time PCR were used to detect Tβ4 methylation frequency and mRNA level. The expression of Tβ4 was measured before and after glucocorticoid treatment in patients with ACHBLF. Clinical and laboratory parameters were obtained.

RESULTS

Tβ4 mRNA expression of patients with ACHBLF was lower than in patients with CHB or HCs, but the methylation frequency was higher. Tβ4 promoter methylation frequency was correlated with serum total bilirubin, prothrombin activity and model for end-stage liver disease score. Moreover, Tβ4 promoter methylation frequency decreased and demethylation occurred during glucocorticoid therapy. After glucocorticoid therapy, Tβ4 mRNA expression and liver function were better in patients with low levels of methylation than in those with higher levels. After 90 d, the survival of patients with low levels of methylation was significantly higher than those with high levels.

CONCLUSIONS

Patients with ACHBLF who have low levels of Tβ4 methylation may show a more favorable response to glucocorticoid treatment.

Improving Lipophagy by Restoring Rab7 Cycle: Protective Effects of Quercetin on Ethanol-Induced Liver Steatosis

Chronic alcohol consumption retards lipophagy, which contributes to the pathogenesis of liver steatosis. Lipophagy-related Rab7 has been presumed as a crucial regulator in the progression of alcohol liver disease despite elusive mechanisms. More importantly, whether or not hepatoprotective quercetin targets Rab7-associated lipophagy disorder is unknown. Herein, alcoholic fatty liver induced by chronic-plus-single-binge ethanol feeding to male C57BL/6J mice was manifested by hampering autophagosomes formation with lipid droplets and fusion with lysosomes compared with the normal control, which was normalized partially by quercetin. The GST-RILP pulldown assay of Rab7 indicated an improved GTP-Rab7 as the quercetin treatment for ethanol-feeding mice. HepG2 cells transfected with CYP2E1 showed similar lipophagy dysfunction when exposed to ethanol, which was blocked when cells were transfected with siRNA-Rab7 in advance. Ethanol-induced steatosis and autophagic flux disruption were aggravated by the Rab7-specific inhibitor CID1067700 while alleviated by transfecting with the Rab7Wt plasmid, which was visualized by immunofluorescence co-localization analysis and mCherry-GFP-LC3 transfection. Furthermore, TBC1D5, a Rab GTPase-activating protein for the subsequent normal circulation of Rab7, was downregulated after alcohol administration but regained by quercetin. Rab7 circulation retarded by ethanol and corrected by quercetin was further revealed by fluorescence recovery after photobleaching (FRAP). Altogether, quercetin attenuates hepatic steatosis by normalizing ethanol-imposed Rab7 turnover disorders and subsequent lipophagy disturbances, highlighting a novel mechanism and the promising prospect of quercetin-like phytochemicals against the crucial first hit from alcohol.

Discovery of thymosin β4 as a human exerkine and growth factor

Skeletal muscle is an endocrine organ secreting exercise-induced factors (exerkines), which play a pivotal role in interorgan cross talk. Using mass spectrometry (MS)-based proteomics, we characterized the secretome and identified thymosin β4 (TMSB4X) as the most upregulated secreted protein in the media of contracting C2C12 myotubes. TMSB4X was also acutely increased in the plasma of exercising humans irrespective of the insulin resistance condition or exercise mode. Treatment of mice with TMSB4X did not ameliorate the metabolic disruptions associated with diet induced-obesity, nor did it enhance muscle regeneration in vivo. However, TMSB4X increased osteoblast proliferation and neurite outgrowth, consistent with its WADA classification as a prohibited growth factor. Therefore, we report TMSB4X as a human exerkine with a potential role in cellular cross talk.

Thymosin β4 Suppresses LPS-Induced Murine Lung Fibrosis by Attenuating Oxidative Injury and Alleviating Inflammation

Inflammation plays a critical role in the progression of pulmonary fibrosis. Thymosin β4 (Tβ4) has antioxidant, anti-inflammatory, and antifibrotic effects. Although the potent protective role of Tβ4 in bleomycin-induced pulmonary fibrosis has been validated, the underlying mechanism is not clear; moreover, the influence of Tβ4 on lipopolysaccharide (LPS)-induced lung injury/fibrosis has not been reported. Expression of Tβ4 in fibrotic lung tissues was assessed by real-time quantitative reverse-transcription PCR (rt-PCR), immunohistochemistry (IHC), and western blotting. The effects of intraperitoneal adeno-associated virus-Tβ4 (AAV-Tβ4) on LPS-induced lung injury and fibrosis were observed through the evaluation of collagen deposition and α-smooth muscle actin (SMA) expression. In vitro tests with HPAEpiC and HLF-1 cells were performed to confirm the effects of Tβ4. In this study, we evaluated the role of Tβ4 in pulmonary fibrosis and explored the possible underlying mechanisms. Tβ4 was markedly upregulated in human or mouse fibrotic lung tissues. AAV-Tβ4 markedly alleviated LPS-induced oxidative damage, lung injury, inflammation, and fibrosis in mice. Our in vitro experiments also showed that LPS inhibited mitophagy and promoted inflammation via oxidative stress in HPAEpiC, and Tβ4 significantly attenuated LPS-induced mitophagy inhibition, inflammasome activation, and transforming growth factor-β (TGF)-β1-induced epithelial-mesenchymal transition (EMT) in HPAEpiC. Moreover, Tβ4 suppressed the proliferation and attenuated the TGF-β1-induced activation of HLF-1 cells. In conclusion, Tβ4 alleviates LPS-induced lung injury, inflammation, and subsequent fibrosis in mice, suggesting that Tβ4 has a protective role in the pathogenesis of pulmonary fibrosis. Tβ4 is involved in attenuating oxidative injury, promoting mitophagy, and alleviating inflammation and fibrosis. Modulation of Tβ4 might be a novel strategy for treating pulmonary fibrosis.

Actin-Binding Proteins as Potential Biomarkers for Chronic Inflammation-Induced Cancer Diagnosis and Therapy

Actin-binding proteins (ABPs), by interacting with actin, regulate the polymerization, depolymerization, bundling, and cross-linking of actin filaments, directly or indirectly, thereby mediating the maintenance of cell morphology, cell movement, and many other biological functions. Consequently, these functions of ABPs help regulate cancer cell invasion and metastasis when cancer occurs. In recent years, a variety of ABPs have been found to be abnormally expressed in various cancers, indicating that the detection and interventions of unusual ABP expression to alter this are available for the treatment of cancer. The early stages of most cancer development involve long-term chronic inflammation or repeated stimulation. This is the case for breast cancer, gastric cancer, lung cancer, prostate cancer, liver cancer, esophageal cancer, pancreatic cancer, melanoma, and colorectal cancer. This article discusses the relationship between chronic inflammation and the above-mentioned cancers, emphatically introduces relevant research on the abnormal expression of ABPs in chronic inflammatory diseases, and reviews research on the expression of different ABPs in the above-mentioned cancers. Furthermore, there is a close relationship between ABP-induced inflammation and cancer. In simple terms, abnormal expression of ABPs contributes to the chronic inflammation developing into cancer. Finally, we provide our viewpoint regarding these unusual ABPs serving as potential biomarkers for chronic inflammation-induced cancer diagnosis and therapy, and interventions to reverse the abnormal expression of ABPs represent a potential approach to preventing or treating the corresponding cancers.

A polysaccharide of PFP-1 from Pleurotus geesteranus attenuates alcoholic liver diseases via Nrf2 and NF-κB signaling pathways

A polysaccharide named PFP-1 was isolated from the Pleurotus geesteranus fruiting body, and potential investigations on ameliorating oxidative stress and liver injury against alcoholic liver disease (ALD) were performed in mice. The animal studies demonstrated that PFP-1 had hepatoprotective effects by improving hepatocellular histopathology, modulating alcohol metabolisms and restoring the serum lipid levels. Besides, PFP-1 could attenuate oxidative stress and inflammatory responses by activating the Nrf2-mediated signal pathways and regulating the TLR4-mediated NF-κB signal pathways. The characterization indicated that PFP-1 was a typical pyranose-polysaccharide in a triple-helical conformation, which was linked by t-β-Glcp, 1,6-α-Glcp and 1,2,6-α-Galp. And the characteristic properties of higher water solubility and appropriate molecular weights contributed to the superior bioactivities. The results demonstrated that PFP-1 could be used as a supplement for alleviating alcohol-induced liver damage.

Alcoholic and Non-Alcoholic Liver Diseases: Promising Molecular Drug Targets and their Clinical Development

Alcoholic and non-alcoholic fatty liver diseases have become a serious concern worldwide. Both these liver diseases have an identical pathology, starting from simple steatosis to cirrhosis and, ultimately to hepatocellular carcinoma. Treatment options for alcoholic liver disease (ALD) are still the same as they were 50 years ago which include corticosteroids, pentoxifylline, antioxidants, nutritional support and abstinence; and for non-alcoholic fatty liver disease (NAFLD), weight loss, insulin sensitizers, lipid-lowering agents and anti-oxidants are the only treatment options. Despite broad research in understanding the disease pathophysiology, limited treatments are available for clinical use. Some therapeutic strategies based on targeting a specific molecule have been developed to lessen the consequences of disease and are under clinical investigation. Therefore, focus on multiple molecular targets will help develop an efficient therapeutic strategy. This review comprises a brief overview of the pathogenesis of ALD and NAFLD; recent molecular drug targets explored for ALD and NAFLD that may prove to be effective for multiple therapeutic regimens and also the clinical status of these promising drug targets for liver diseases.

Effect of Food Endotoxin on Infant Health

Endotoxin is a complex molecule derived from the outer membrane of Gram-negative bacteria, and it has strong thermal stability. The processing of infant food can kill pathogenic bacteria but cannot remove endotoxin. Because the intestinal structure of infants is not fully developed, residual endotoxin poses a threat to their health by damaging the intestinal flora and inducing intestinal inflammation, obesity, and sepsis, among others. This paper discusses the sources and contents of endotoxin in infant food and methods for preventing endotoxin from harming infants. However, there is no clear evidence that endotoxin levels in infant food cause significant immune symptoms or even diseases in infants. However, in order to improve the safety level of infant food and reduce the endotoxin content, this issue should not be ignored. The purpose of this review is to provide a theoretical basis for manufacturers and consumers to understand the possible harm of endotoxin content in infant formula milk powder and to explore how to reduce its level in infant formula milk powder. Generally, producers should focus on cleaning the milk source, securing the cold chain, avoiding long-distance transportation, and shortening the storage time of raw milk to reduce the level of bacteria and endotoxin. After production and processing, the endotoxin content should be measured as an important index to test the quality of infant formula milk powder so as to provide high-quality infant products for the healthy growth of newborns.

Recombinant Human Thymosin Beta-4 Protects against Mouse Coronavirus Infection

Coronaviruses (CoVs) are enveloped and harbor an unusually large (30-32 kb) positive-strand linear RNA genome. Highly pathogenic coronaviruses cause severe acute respiratory syndrome (SARS) (SARS-CoV and SARS-CoV-2) and Middle East respiratory syndrome (MERS) (MERS-CoV) in humans. The coronavirus mouse hepatitis virus (MHV) infects mice and serves as an ideal model of viral pathogenesis, mainly because experiments can be conducted using animal-biosafety level-2 (A-BSL2) containment. Human thymosin beta-4 (Tβ4), a 43-residue peptide with an acetylated N-terminus, is widely expressed in human tissues. Tβ4 regulates actin polymerization and functions as an anti-inflammatory molecule and an antioxidant as well as a promoter of wound healing and angiogenesis. These activities led us to test whether Tβ4 serves to treat coronavirus infections of humans. To test this possibility, here, we established a BALB/c mouse model of coronavirus infection using mouse CoV MHV-A59 to evaluate the potential protective effect of recombinant human Tβ4 (rhTβ4). Such a system can be employed under A-BSL2 containment instead of A-BSL3 that is required to study coronaviruses infectious for humans. We found that rhTβ4 significantly increased the survival rate of mice infected with MHV-A59 through inhibiting virus replication, balancing the host's immune response, alleviating pathological damage, and promoting repair of the liver. These results will serve as the basis for further application of rhTβ4 to the treatment of human CoV diseases such as COVID-19.

Association between MeCP2 and Smad7 in the pathogenesis and development of pathological scars

To explore the relationship between methylated binding protein 2 (MeCP2) and mothers against decapentaplegic homolog 7 (Smad7) in the pathogenesis and development of pathological scars. Immunohistochemistry, Western blot and real-time polymerase chain reaction (RT-PCR) were used to detect the expression of MeCP2 in different types of human scars and hypertrophic scars at different growth times. The methylation status of Smad7 gene promoter in different scar tissues was determined by methylation-specific PCR. After transfection with MeCP2-siRNA (small interfering RNA) in human keloid fibroblasts, MTT assay was used to assess the proliferation activity of keloid fibroblasts, while RT-PCR and Western blot assays were used to detect the expression levels of MeCP2, transforming growth factor-β1 (TGF-β1), α-smooth muscle actin (α-SMA), phospho-Smad2 (p-Smad2) and Smad7. MeCP2 was mainly expressed in the nucleus of fibroblasts. The mRNA and protein levels of MeCP2 were significantly higher in keloids than in hypertrophic scars, normal scars and normal skin (p<.05). The expression level of MeCP2 in hypertrophic scars during the growth period of <6 months was markedly higher than that of >6 months (p<.05). The methylation level of Smad7 was significantly higher in keloids compared to normal skin. After MeCP2 silencing, the proliferation rate of human keloid fibroblasts was decreased, the mRNA and protein levels of Smad7 were increased, and the expression levels of TGF-β1, α-SMA and p-Smad2 were decreased (p<.05). MeCP2 and Smad7 play an important role in formation of pathological scars. During keloid formation, MeCP2 weakens the inhibitory effect of Smad7 on p-Smad2/3 by downregulating the expression of Smad7, which in turn promotes fibrosis and scar hyperplasia.

Cardiomyocytes stimulate angiogenesis after ischemic injury in a ZEB2-dependent manner

The disruption in blood supply due to myocardial infarction is a critical determinant for infarct size and subsequent deterioration in function. The identification of factors that enhance cardiac repair by the restoration of the vascular network is, therefore, of great significance. Here, we show that the transcription factor Zinc finger E-box-binding homeobox 2 (ZEB2) is increased in stressed cardiomyocytes and induces a cardioprotective cross-talk between cardiomyocytes and endothelial cells to enhance angiogenesis after ischemia. Single-cell sequencing indicates ZEB2 to be enriched in injured cardiomyocytes. Cardiomyocyte-specific deletion of ZEB2 results in impaired cardiac contractility and infarct healing post-myocardial infarction (post-MI), while cardiomyocyte-specific ZEB2 overexpression improves cardiomyocyte survival and cardiac function. We identified Thymosin β4 (TMSB4) and Prothymosin α (PTMA) as main paracrine factors released from cardiomyocytes to stimulate angiogenesis by enhancing endothelial cell migration, and whose regulation is validated in our in vivo models. Therapeutic delivery of ZEB2 to cardiomyocytes in the infarcted heart induces the expression of TMSB4 and PTMA, which enhances angiogenesis and prevents cardiac dysfunction. These findings reveal ZEB2 as a beneficial factor during ischemic injury, which may hold promise for the identification of new therapies.

Progress on the Function and Application of Thymosin β4

Thymosin β4 (Tβ4) is a multifunctional and widely distributed peptide that plays a pivotal role in several physiological and pathological processes in the body, namely, increasing angiogenesis and proliferation and inhibiting apoptosis and inflammation. Moreover, Tβ4 is effectively utilized for several indications in animal experiments or clinical trials, such as myocardial infarction and myocardial ischemia-reperfusion injury, xerophthalmia, liver and renal fibrosis, ulcerative colitis and colon cancer, and skin trauma. Recent studies have reported the potential application of Tβ4 and its underlying mechanisms. The present study reveals the progress regarding functions and applications of Tβ4.

Dual Effect of Soloxolone Methyl on LPS-Induced Inflammation In Vitro and In Vivo

Plant-extracted triterpenoids belong to a class of bioactive compounds with pleotropic functions, including antioxidant, anti-cancer, and anti-inflammatory effects. In this work, we investigated the anti-inflammatory and anti-oxidative activities of a semisynthetic derivative of 18βH-glycyrrhetinic acid (18βH-GA), soloxolone methyl (methyl 2-cyano-3,12-dioxo-18βH-olean-9(11),1(2)-dien-30-oate, or SM) in vitro on lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages and in vivo in models of acute inflammation: LPS-induced endotoxemia and carrageenan-induced peritonitis. SM used at non-cytotoxic concentrations was found to attenuate the production of reactive oxygen species and nitric oxide (II) and increase the level of reduced glutathione production by LPS-stimulated RAW264.7 cells. Moreover, SM strongly suppressed the phagocytic and migration activity of activated macrophages. These effects were found to be associated with the stimulation of heme oxigenase-1 (HO-1) expression, as well as with the inhibition of nuclear factor-κB (NF-κB) and Akt phosphorylation. Surprisingly, it was found that SM significantly enhanced LPS-induced expression of the pro-inflammatory cytokines interleukin-6 (IL-6), tumour necrosis factor-α (TNF-α), and interleukin-1β (IL-1β) in RAW264.7 cells via activation of the c-Jun/Toll-like receptor 4 (TLR4) signaling axis. In vivo pre-exposure treatment with SM effectively inhibited the development of carrageenan-induced acute inflammation in the peritoneal cavity, but it did not improve LPS-induced inflammation in the endotoxemia model.

S-allyl cysteine, an active ingredient of garlic, attenuates acute liver dysfunction induced by lipopolysaccharide/ d-galactosamine in mouse: Underlying mechanisms

In the present study, beneficial effect of S-allyl cysteine (SAC) was evaluated in the lipopolysaccharide/d-galactosamine (LPS/d-Gal) model of acute liver injury (ALI). To mimic ALI, LPS and d-Gal (50 μg/kg and 400 mg/kg, respectively) were intraperitoneally administered and animals received SAC per os (25 or 100 mg/kg/d) for 3 days till 1 hour before LPS/d-Gal injection. Pretreatment of LPS/d-Gal group with SAC-lowered activities of alkaline phosphatase, alanine aminotransferase, and aspartate aminotransferase and partially reversed inappropriate alterations of hepatic oxidative stress- and inflammation-related biomarkers including liver reactive oxygen species, malondialdehyde, and hepatic activity of the defensive enzyme superoxide dismutase, ferric reducing antioxidant power (FRAP), toll-like receptor-4 (TLR4), cyclooxygenase 2, NLR family pyrin domain containing 3 (NLRP3), caspase 1, nuclear factor κB (NF-κB), interleukin 1β (IL-1β), IL-6, tumor necrosis factor-α, and myeloperoxidase activity. Additionally, SAC was capable to ameliorate apoptotic biomarkers including caspase 3 and DNA fragmentation. In summary, SAC can protect liver against LPS/d-Gal by attenuation of neutrophil infiltration, oxidative stress, inflammation, apoptosis, and pyroptosis which is partly linked to its suppression of TLR4/NF-κB/NLRP3 signaling.

The Effect of Thymosin beta4 on the Survival of Autologous Fat Grafting: A Preliminary Study

BACKGROUND

Autologous fat grafting is a common procedure to improve tissue deficiencies. However, the survival rate of fat grafting is unpredictable. Thymosin beta 4 (Tß4), a multifunctional peptide containing 43 amino acids, is effective in angiogenesis, inhibiting apoptosis and inflammation.

OBJECTIVES

The authors initially investigated the potential effect of Tß4 in fat grafting.

METHODS

Adipose tissue premixed exogenous Tß4 were transplanted into rabbit ears. Rabbits were randomly assigned to 3 groups: group A, 5 μg/mL Tß4; group B, 10 μg/mL Tß4; and group C, phosphate-buffered saline buffer as a blank control. The fat grafts were subjected to magnetic resonance imaging at 2, 4, and 12 weeks in vivo. Each harvested graft was analyzed at 3 time points after transplantation.

RESULTS

The fat grafts in the Tß4-treated groups showed better volume and weight retention, greater adipose tissue integrity, adipocyte viability, and angiogenesis. The results of dynamic contrast-enhanced magnetic resonance imaging also showed that the experimental groups increased microcirculation perfusion of the grafts.

CONCLUSIONS

The study proved that Tß4 could improve adipose tissue survival and neovascularization. It may be useful for fat grafting as a potential protective reagent.

Environmental contaminant ammonia triggers epithelial-to-mesenchymal transition-mediated jejunal fibrosis with the disassembly of epithelial cell-cell contacts in chicken

Ammonia (NH₃) is an environmental contaminant that is causing increasing problems with human and animal health due to the development of poultry industry. There are limited studies on the effect of NH₃ inhalation toxicity on the intestinal tract of animals, and underlying molecular mechanisms remain unclear. In the present study, we established a chicken model of NH₃ aspiration-induced injury for 42 days and observed histopathological changes of the jejunum. Tandem mass tag-based quantitative proteomic analysis was applied to investigate changes in the protein profile in the jejunum tissue of chickens that were exposed to NH₃. Overall, 48 significantly differentially expressed proteins (DEPs) were identified. GO and KEGG analyses revealed that most DEPs were closely related to epithelial-to-mesenchymal transition (EMT), cell-cell junctions, and fibrosis-related factors. Regarding fibrosis, type I collagen and fibronectin were significantly increased. With respect to EMT, epithelial marker proteins (such as E-cadherin and keratin) were repressed, while mesenchymal marker proteins (such as vimentin) were activated. Loss of epithelial cell-cell junctions (such as tight junctions, adherens junctions and desmosomes) were observed. Additionally, overexpression of transforming growth factor-beta (TGF-β) may play a key role in the EMT process and fibrosis. Taken together, these findings suggested that NH₃ triggered the EMT and disassembly of epithelial cell-cell contacts, resulting in jejunal fibrosis that was mediated by TGF-β in chickens. The results of our study will contribute to provide a technical reference regarding the research methods of intestinal toxicity of NH₃ and have largely regulatory implications for ecological risk assessment of human health.

Tβ4 suppresses lincRNA-p21-mediated hepatic apoptosis and fibrosis by inhibiting PI3K-AKT-NF-κB pathway

Hepatic injury is one of the most challenging diseases in clinical medicine. Hepatic injury is accompanied by hepatocyte apoptosis and leads to hepatic fibrosis and cirrhosis, which may cause liver cancer and increased mortality. Therefore, it is essential to investigate the regulation mechanism and therapeutic strategies for hepatic injury. In the study, the effects of Thymosin β4 (Tβ4) on Long intergenic noncoding RNA-p21 (lincRNA-p21)-mediated liver injury were investigated. Results showed that lincRNA-p21 overexpression promoted hepatocytes apoptosis, which was blocked by Tβ4. Besides, Tβ4 reversed the levels of cleaved caspase-3 and caspase-9 induced by lincRNA-p21. LincRNA-p21 overexpression also caused the pathological injury and fibrosis in hepatic tissues and increased the levels of fibrosis-related proteins (Collagen I, α-SMA and TIMP-1), and induced hydroxyproline and ALT production. However, Tβ4 reversed the effects of overexpression of lincRNA-p21 on hepatic injury and fibrosis. In vitro experiments, after lincRNA-p21 was overexpressed in hepatic stellate cells (HSCs), the proliferation ability and the levels of HSCs markers α-SMA and Desmin were increased. However, Tβ4 reversed the effects of lincRNA-p21 on HSCs. Furthermore, the PI3K-AKT-NF-κB pathway was activated by lincRNA-p21, which was then reversed by the Tβ4 administration. After the mice treated by insulin-like growth factor-1 (IGF-1) (the activator of PI3K-AKT), the inhibitory effect of Tβ4 on activated the PI3K-AKT-NF-κB pathway was abrogated. Besides, IGF-1 abolished the protective effects of Tβ4 on hepatic apoptosis and fibrosis induced by lincRNA-p21. Therefore, Tβ4 reversed. lincRNA-p21-mediated liver injury through inhibiting PI3K-AKT-NF-κB pathway. Tβ4 may be a promising drug for fibrosis therapy.

Imbalance in mitochondrial dynamics induced by low PGC-1α expression contributes to hepatocyte EMT and liver fibrosis

An imbalance in mitochondrial dynamics induced by oxidative stress may lead to hepatocyte epithelial mesenchymal transition (EMT) and liver fibrosis. However, the underlying molecular mechanisms have not been fully elucidated. This study investigated the role of mitochondrial dynamics in hepatocyte EMT and liver fibrosis using an in vitro human (L-02 cells, hepatic cell line) and an in vivo mouse model of liver fibrosis. Findings showed that oxidative stress-induced mitochondrial DNA damage was associated with abnormal mitochondrial fission and hepatocyte EMT. The reactive oxygen species (ROS) scavengers apocynin and mito-tempo effectively attenuated carbon tetrachloride (CCl4)-induced abnormal mitochondrial fission and liver fibrosis. Restoring mitochondrial biogenesis attenuated hepatocyte EMT. Oxidative stress-induced abnormal hepatocyte mitochondrial fission events by a mechanism that involved the down regulation of PGC-1α. PGC-1α knockout mice challenged with CCl4 had increased abnormal mitochondrial fission and more severe liver fibrosis than wild type mice. These results indicate that PGC-1α has a protective role in oxidative stress-induced-hepatocyte EMT and liver fibrosis.

Anti-inflammatory effects of glycine thymosin β4 eye drops in experimental dry eye

The aim of the present study was to investigate the anti-inflammatory effects of glycine thymosin β4 (Gly-Tβ4) eye drops, and to compare the efficacy of topical Gly-Tβ4 with Cyclosporine A (CsA) in a mouse model of experimental dry eye (EDE). Eye drops consisting of balanced salt solution (BSS), 0.1% Gly-Tβ4 or 0.05% CsA were used for treatment of EDE. Tear volume, tear film break-up time and corneal staining scores were measured after 7 and 14 days. Periodic acid-Schiff staining for conjunctival gobleT cells, TUNEL assay for corneal apoptotic positive cells, multiplex immunobead assay for interleukin (IL)-1β, IL-6, tumor necrosis factor-α and interferon-γ levels, and flow cytometry for CD4⁺/CCR5⁺ T cells were performed after 14 days. All clinical parameters showed improvement in the Gly-Tβ4 and CsA groups (all P<0.05). Significantly increased conjunctival gobleT cells and decreased corneal TUNEL positive cells were observed in the Gly-Tβ4 and CsA groups. The Gly-Tβ4 and CsA treated groups showed significantly reduced inflammatory cytokine levels and T cells in the conjunctiva compared with the EDE and BSS groups (all P<0.05). However, there were no significant differences observed in the inflammatory and clinical parameters between the Gly-Tβ4 and CsA treatment groups. Topical application of 0.1% Gly-Tβ4 significantly reduced inflammation on the ocular surface, as well as clinical parameters of EDE, with a similar efficacy to that of 0.05% CsA emulsions, suggesting that Gly-Tβ4 eye drops may be used as a therapeutic agent for treatment of dry eye disease.

Tβ4-Ac-SDKP pathway: Any relevance for the cardiovascular system?

The last 20 years witnessed the emergence of the thymosin β4 (Tβ4)-N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) pathway as a new source of future therapeutic tools to treat cardiovascular and renal diseases. In this review article, we attempted to shed light on the numerous experimental findings pertaining to the many promising cardiovascular therapeutic avenues for Tβ4 and (or) its N-terminal derivative, Ac-SDKP. Specifically, Ac-SDKP is endogenously produced from the 43-amino acid Tβ4 by 2 successive enzymes, meprin α and prolyl oligopeptidase. We also discussed the possible mechanisms involved in the Tβ4-Ac-SDKP-associated cardiovascular biological effects. In infarcted myocardium, Tβ4 and Ac-SDKP facilitate cardiac repair after infarction by promoting endothelial cell migration and myocyte survival. Additionally, Tβ4 and Ac-SDKP have antifibrotic and anti-inflammatory properties in the arteries, heart, lungs, and kidneys, and stimulate both in vitro and in vivo angiogenesis. The effects of Tβ4 can be mediated directly through a putative receptor (Ku80) or via its enzymatically released N-terminal derivative Ac-SDKP. Despite the localization and characterization of Ac-SDKP binding sites in myocardium, more studies are needed to fully identify and clone Ac-SDKP receptors. It remains promising that Ac-SDKP or its degradation-resistant analogs could serve as new therapeutic tools to treat cardiac, vascular, and renal injury and dysfunction to be used alone or in combination with the already established pharmacotherapy for cardiovascular diseases.

Mangiferin improves hepatic damage-associated molecular patterns, lipid metabolic disorder and mitochondrial dysfunction in alcohol hepatitis rats

This study was conducted to investigate the beneficial effects and possible mechanism of action of mangiferin (MF) in alcohol hepatitis (AH) rats. Building on our previous study, the damage-associated molecular patterns (DAMPs), lipid metabolic disorder and mitochondrial dysfunction were investigated. MF effectively regulated the abnormal liver function, the levels of alcohol, FFAs and metal elements in serum. More importantly, MF improved the expression levels of mRNA and protein of PPAR-γ, OPA-1, Cav-1, EB1, NF-κB p65, NLRP3, Cas-1 and IL-1β, and decreased the positive protein expression rates of HSP90, HMGB1, SYK, CCL20, C-CAS-3, C-PARP and STARD1. Additionally, MF decreased the levels of fumarate, cAMP, xanthurenic acid and d-glucurone-6,3-lactone, and increased the levels of hippuric acid and phenylacetylglycine, and then adjusted the changes of phenylalanine metabolism, TCA cycle and ascorbate and aldarate metabolic pathways. The above results suggested that MF can effectively prevent AH by modulating specific AH-associated genes, potential biomarkers and metabolic pathways in AH rats, etc.

Protective Effect of Thymosin β4 against Abdominal Aortic Ischemia-Reperfusion-Induced Acute Lung Injury in Rats

Background and objectives: Ischemia-reperfusion (IR) caused by infrarenal abdominal aorta cross-clamping is an important factor in the development of ischemia-reperfusion injury in various distant organs. Materials and Methods: We investigated potential antioxidant/anti-inflammatory effects of thymosin beta 4 (Tβ4) in a rat model of abdominal aortic surgery-induced IR. Tβ4 (10 mg/kg, intravenous (i.v.)) was administered to rats with IR (90-min ischemia, 180-min reperfusion) at two different periods. One group received Tβ4 1 h before ischemia, and the other received 15 min before the reperfusion period. Results: Results were compared to control and non-Tβ4-treated rats with IR. Serum, bronchoalveolar lavage fluid and lung tissue levels of oxidant parameters were higher, while antioxidant levels were lower in the IR group compared to control. IR also increased inflammatory cytokine levels. Tβ4 reverted these parameters in both Tβ4-treated groups compared to the untreated IR group. Conclusions: Since there is no statistical difference between the prescribed results of both Tβ4-treated groups, our study demonstrates that Tβ4 reduced lung oxidative stress and inflammation following IR and prevented lung tissue injury regardless of timing of administration.

ROS-Induced GATA4 and GATA6 Downregulation Inhibits StAR Expression in LPS-Treated Porcine Granulosa-Lutein Cells

LPS is a major endotoxin produced by gram-negative bacteria, and exposure to it commonly occurs in animal husbandry. Previous studies have shown that LPS infection disturbs steroidogenesis, including progesterone production, and subsequently decreases animal reproductive performance. However, little information about the underlying mechanisms is available thus far. In the present study, an in vitro-luteinized porcine granulosa cell model was used to study the underlying molecular mechanisms of LPS treatment. We found that LPS significantly inhibits progesterone production and downregulates the expressions of progesterone synthesis-associated genes (StAR, CYP11A1, and 3β-HSD). Furthermore, the levels of ROS were significantly increased in an LPS dose-dependent manner. Moreover, transcriptional factors GATA4 and GATA6, but not NR5A1, were significantly downregulated. Elimination of LPS-stimulated ROS by melatonin or vitamin C could restore the expressions of GATA4, GATA6, and StAR. In parallel, StAR expression was also inhibited by the knockdown of GATA4 and GATA6. Based on these data, we conclude that LPS impairs StAR expression via the ROS-induced downregulation of GATA4 and GATA6. Collectively, these findings provide new insights into the understanding of reproductive losses in animals suffering from bacterial infection and LPS exposure.

Thymosin participates in antimicrobial immunity in zebrafish

Thymosin hormones, which were shown to be involved in immune system development and differentiation in previous studies, have antimicrobial functions in different animals. Zebrafish are a useful model for immunology research. Although thymosin has been reported to be involved in the embryonic development of zebrafish, it is necessary to uncover the antimicrobial function of thymosin in zebrafish. In this study, we expressed thymosin β (Tβ) in zebrafish in vitro and studied its antimicrobial function. The Tβ protein consists of 45 amino acids and is conserved among its family members, especially the actin-binding motif (LKKTET). Tβ was expressed in all tested tissues and was highly expressed in the brain, liver and hindgut. After Aeromonas hydrophila challenge, the Tβ transcript level increased in the skin, liver, kidney, spleen, thymus, foregut, gills and midgut. Purified recombinant thymosin β (rTβ) protein was used to study the antimicrobial mechanism. rTβ could inhibit the growth of Staphylococcus aureus, Aeromonas hydrophila, Vibrio anguillarum, Pseudomonas aeruginosa and Klebsiella pneumoniae. rTβ also binds to and agglutinates certain bacteria. Further study showed that rTβ could combine with the polysaccharides from gram-negative and gram-positive bacterial walls. All results suggested that the Tβ of zebrafish plays a significant role in innate antibacterial immune responses.

A New Era of Cardiac Cell Therapy: Opportunities and Challenges

Myocardial infarction (MI), caused by coronary heart disease (CHD), remains one of the most common causes of death in the United States. Over the last few decades, scientists have invested considerable resources on the study and development of cell therapies for myocardial regeneration after MI. However, due to a number of limitations, they are not yet readily available for clinical applications. Mounting evidence supports the theory that paracrine products are the main contributors to the regenerative effects attributed to these cell therapies. The next generation of cell-based MI therapies will identify and isolate cell products and derivatives, integrate them with biocompatible materials and technologies, and use them for the regeneration of damaged myocardial tissue. This review discusses the progress made thus far in pursuit of this new generation of cell therapies. Their fundamental regenerative mechanisms, their potential to combine with other therapeutic products, and their role in shaping new clinical approaches for heart tissue engineering, are addressed.