Platelet-derived Growth Factor Subunit Research Articles

Accelerated BDNF expression in visceral white adipose tissues following high-fat diet feeding in mice.

Brain-derived neurotrophic factor (BDNF) is expressed in the white adipose tissues (WATs), and the expression increases during high-fat diet (HFD) feeding, implicating its role in obesity. Here, we focused on BDNF expression in epididymal WAT (eWAT), a visceral adipose tissue, in mice. During 2 weeks of HFD feeding, Bdnf mRNA expression in eWAT slightly increased, but a robust increase was observed after 8 weeks of HFD feeding. This upregulation of Bdnf mRNA was correlated with significant induction of hypoxia-inducible factor 1α (Hif1α) and platelet-derived growth factor subunit B (Pdgfb) mRNA in eWAT following 8 weeks of HFD feeding. Furthermore, the increased expression of the M1 macrophage markers was strongly correlated with the elevation of Bdnf mRNA in the eWAT. Notably, 8 weeks of HFD feeding significantly elevated Tnfα mRNA expression in eWAT, while no such induction was observed in inguinal WAT (iWAT). In contrast, the expression of Adipoq (adiponectin), implicated in improved insulin sensitivity and anti-inflammatory effects, was significantly upregulated in iWAT, but not in eWAT. Thus, our study may show the role of BDNF in eWAT in obesity models, potentially contributing to the pathological state of visceral adipose tissues.

Inhibiting endothelial Rhoj blocks profibrotic vascular intussusception and angiocrine factors to sustain lung regeneration.

Lung regeneration after fibrosis requires formation of functional new vasculature, which is essential for gas exchange and cellular cross-talk with other lung cells. It remains unknown how the lung vasculature can be regenerated without fibrosis. Here, we tested the role of N6-methyladenosine (m6A) modification of forkhead box protein O1 (Foxo1) mRNA in lung regeneration after pneumonectomy (PNX) in mice, a model for lung regrowth after surgical resection. Endothelial cell (EC)-specific knockout of methyltransferase-like 3 (Mettl3) and Foxo1 caused nonproductive intussusceptive angiogenesis (IA), which impaired regeneration and enhanced fibrosis. This nonproductive IA was characterized by enhanced endothelial proliferation and increased vascular splitting with increased numbers of pillar ECs. Endothelial-selective knockout of Mettl3 in mice stimulated nonproductive IA and up-regulation of profibrotic factors after PNX, promoting regeneration to fibrotic transition. EC-specific mutation of m6A modification sites in the Foxo1 gene in mice revealed that endothelial Mettl3 modified A504 and A2035 sites in the Foxo1 mRNA to maintain pro-regenerative endothelial glycolysis, ensuring productive IA and lung regeneration without fibrosis. Suppression of Mettl3-Foxo1 signaling stimulated a subset of hyperglycolytic and hyperproliferative 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (Pfkfb3)+, Ras homolog family member J (Rhoj)+, and platelet-derived growth factor subunit B (Pdgfb)+ ECs in both human and mouse lungs with fibrosis. Inhibiting this Pfkfb3+Rhoj+Pdgfb+ EC subset normalized IA, alleviated fibrosis, and restored regeneration in bleomycin (BLM)-injured mouse lungs. We found that m6A modification of Foxo1 in the mouse vasculature promoted lung regeneration over fibrosis after PNX and BLM injury.

Inhibition of myotube formation by platelet-derived growth factor subunit B in QM7 cells.

The primary objective of this study was to investigate the role and regulatory mechanisms of Platelet-derived Growth Factor Subunit B (PDGFB) in muscle differentiation. In this study, a vector for PDGFB was designed and transfected into quail muscle cells to investigate its role and regulatory mechanism during muscle formation. To investigate the inhibitory mechanisms of PDGFB on myogenic differentiation, the mRNA expression levels of various genes and the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK 1/2), both known to regulate muscle development and differentiation were compared. PDGFB-overexpressed (OE) cells formed morphologically shorter and thinner myotubes and demonstrated a smaller total myotube area than did the control cells. This result was also confirmed at the molecular level by a reduced amount of myosin heavy chain protein in the PDGFB-OE cells. Therefore, PDGFB inhibits the differentiation of muscle cells. Additionally, the expression of myogenin (MYOG) significantly decreased in the PDGFB-OE cells on days 2 and 4 compared with that in the control cells. The phosphorylation of ERK 1/2, an upstream protein that inhibits MYOG expression, increased in the PDGFB-OE cells on day 4 compared with that in the control cells. The decreased expression of MYOG in the PDGFB-OE cells increased by inhibition ERK 1/2 phosphorylation. PDGFB may suppress myogenesis by reducing MYOG expression through ERK 1/2 phosphorylation. These findings can help understand muscle differentiation and potentially improve poultry meat production.

Cytokine profiles and their roles in development of provoked vulvodynia

Provoked, localized, vulvodynia (PVD) is the main subtype of vulvodynia. Although the etiology of PVD is still a topic of debate, inflammation caused by cytokines responding to a dysregulated microbiome is one of the leading proposed theories. Therefore, the purpose of our study is to further explore the cytokine profiles in the study group with PVD using multiplex immunoassays based on electrochemiluminescence. We compared a panel of 26 distinct cytokines levels in the study group with PVD (n = 23) to the control group (n = 18) and cytokine concentrations were measured using MESO QuickPlex SQ 120 instrument with 5 different multiplex assays. Statistical analysis used the Mann-Whitney U test, two-sided p-values, and a significance level of α = 0.05. Differences in cytokine concentrations are described as negligible, small, medium, or large based on Cliff’s δ. Concentrations of three cytokines were significantly lower in the PVD group: a large difference in IP-10 (p = 0.029*) and medium differences in IL-1RA44Cytokine abbreviations: bFGF; Basic Fibroblast Growth Factor, G-CSF; Granulocyte colony stimulating factor, GM-CSF; Granulocyte-Macrophage Colony-Stimulating Factor, IFN; interferon, IL; Interleukin, IP; Interferon-gamma Inducible Protein, MCP; Monocyte Chemoattractant Protein, MIP; Macrophage Inflammatory Protein, PGDF-BB; Platelet Derived Growth Factor Subunit B, RA; Receptor antagonist, TNF; Tumor Necrosis Factor, VEGF; Vascular Endothelial Growth Factor (p = 0.030*) and IL-12 (p = 0.034*). One cytokine level was significantly higher in the PVD group: a medium difference for IL-6 (p = 0.037*). Due to the lack of consistency in elevation of inflammatory profiles, it is not enough to support persistent inflammation as the etiology behind PVD. However, these findings may indicate there is a possible immune response deficiency in some patients who have PVD. The resemblance of cytokine profile in our study to cytokine profile of people with chronic yeast infection further support this proposed mechanism behind PVD. Future studies involving history and testing for yeast infection are necessary to explore this possibility further.

Function of mast cell and bile-cholangiocarcinoma interplay in cholangiocarcinoma microenvironment

ObjectiveThe correlation between cholangiocarcinoma (CCA) progression and bile is rarely studied. Here, we aimed to identify differential metabolites in benign and malignant bile ducts and elucidate the generation, function and...

Agalactosyl IgG induces liver fibrogenesis via Fc gamma receptor 3a on human hepatic stellate cells.

The relevance of aberrant serum IgG N-glycosylation in liver fibrosis has been identified; however, its causal effect remains unclear. Because hepatic stellate cells (HSCs) contribute substantially to liver fibrosis, we investigated whether and through which mechanisms IgG N-glycosylation affects the fibrogenic properties of HSCs. Analysis of serum IgG1 N-glycome from 151 patients with chronic hepatitis B or liver cirrhosis revealed a positive correlation between Ishak fibrosis grading and IgG1 with agalactosyl N-glycoforms on the crystallizable fragment (Fc). Fc gamma receptor (FcγR) IIIa was observed in cultured human HSCs and HSCs in human liver tissues, and levels of FcγRIIIa in HSCs correlated with the severity of liver fibrosis. Additionally, agalactosyl IgG treatment caused HSCs to have a fibroblast-like morphology, enhanced migration and invasion capabilities, and enhanced expression of the FcγRIIIa downstream tyrosine-protein kinase SYK. Furthermore, agalactosyl IgG treatment increased fibrogenic factors in HSCs, including transforming growth factor (TGF)-β1, total collagen, platelet-derived growth factor subunit B and its receptors, pro-collagen I-α1, α-smooth muscle actin, and matrix metalloproteinase 9. These effects were more pronounced in HSCs that stably expressed FCGR3A and were reduced in FCGR3A knockout cells. Agalactosyl IgG and TGF-β1 each increased FCGR3A in HSCs. Furthermore, serum TGF-β1 concentrations in patients were positively correlated with agalactosyl IgG1 levels and liver fibrosis severity, indicating a positive feedback loop involving agalactosyl IgG, HSC-FcγRIIIa, and TGF-β1. In conclusion, agalactosyl IgG promotes fibrogenic characteristics in HSCs through FcγRIIIa. © 2024 The Pathological Society of Great Britain and Ireland.

Factors for predicting the outcome of surgery for non-eosinophilic chronic rhinosinusitis with nasal polyps

BackgroundDespite the large patient base in Asia, the prognostic factors of patients with non-eosinophilic chronic rhinosinusitis with nasal polyps (CRSwNPs) remain largely undetermined. ObjectiveTo systematically investigate the predictive value of clinical and biological variables for non-eosinophilic CRSwNP. MethodsA total of 51 patients with non-eosinophilic CRSwNP who underwent functional endoscopic surgery were recruited. Clinical information and assessment were comprehensively collected before and after surgery. A broad spectrum of biomarkers was measured in tissue homogenates using multiple assays. A random forest algorithm and stepwise logistic regression were used to construct clinical, biological, and combined models. ResultsA total of 41.2% patients with non-eosinophilic CRSwNP were uncontrolled more than 6 months after surgery. We identified 1 clinical variable (22-item Sino-Nasal Outcome Test score) and 4 biomarkers (programmed cell death ligand 1, platelet-derived growth factor subunit β [PDGF-β], macrophage inflammatory protein-3b, and PDGF-α) that were significantly predictive of the surgical outcome. The clinical, biological, and combined models had predictive ability with areas under the curve of 0.78, 0.83, and 0.89, respectively. PDGF-β and programmed cell death ligand 1 were identified as independent biomarkers for the prognosis of patients with CRSwNP without considerable eosinophilic infiltration. ConclusionThis study reveals that clinical and biological factors, such as the 22-item Sino-Nasal Outcome Test score and PDGF-β, are predictive of the postfunctional endoscopic surgical prognosis of patients with non-eosinophilic CRSwNP.

Proteomics early after heart transplantation and relation to coronary intimal changes and prognosis

BackgroundLong-term survival after heart transplantation (HTx) is limited by cardiac allograft vasculopathy (CAV). The pathogenesis of CAV is poorly understood, and treatment has not yet been well-established. In this exploratory study, we aimed to identify novel immune and non-immune biomarkers correlated to CAV development, and biomarkers predicting CAV related events. MethodsUsing a proteomic panel, 92 cardiovascular disease-related proteins were evaluated in 26 de novo HTx patients at 3- and 12-months post transplantation. Intima area changes were assessed using optical coherence tomography (OCT). Major adverse cardiac events (MACE) included significant CAV progression, heart failure, and cardiovascular death. ResultsMedian follow up was 6.8 years. We found changes in four inflammatory biomarkers: Matrix metalloproteinase 3 (MMP-3) and matrix metalloproteinase 2 (MMP-2) were significantly increased after 3 months in the group of patients with highest intima proliferation, and after 12 months in patients experiencing MACE, respectively. Monocyte chemotactic protein 1 (MCP-1) was increased after 12 months in patients experiencing MACE. Platelet derived growth factor subunit A (PDGF-A) was significantly increased after 3 months in the group of patients with highest intima proliferation. ConclusionsWe identified four biomarkers that may be associated with CAV development which differed significantly between groups of intima proliferation and MACE; MMP-2, MMP-3, MCP-1 and PDGF-A. Further studies are needed to examine whether our findings offer the basis to seek for new markers of graft vasculopathy or treatment options.

Identification of PDGFA as a Neutrophil-related Biomarker Linked to the Advancement of Diabetic Retinopathy through Integrated Bioinformatics Analysis.

The dysregulation of the innate immune system plays a crucial role in the development of Diabetic Retinopathy (DR). To gain an insight into the underlying mechanism of DR, it is essential to identify specific biomarkers associated with immune cell infiltration. In this study, we retrieved the GSE94019 and GSE60436 datasets from the Gene Expression Omnibus (GEO) database. By utilizing CIBERSORT, MCPcounter, and xCell algorithms, we conducted a comprehensive analysis of the immune cell infiltration landscape in DR. The limma package was employed to identify Differentially Expressed Necroptosis-related Genes (DENRGs). Subsequently, enrichment analysis was performed to investigate the potential functions of the DENRGs. To identify the core DENRGs, the CytoHubba plug-in in Cytoscape software was utilized. The expression levels of these core DENRGs were verified in an independent dataset. Our analysis identified 213 DENRGs, and among them, Platelet-derived Growth Factor subunit A (PDGFA) was identified as a core DENRG. Notably, the expression of PDGFA was found to be upregulated in DR, and this finding was further validated in the GSE102485 dataset. Additionally, the results of GSVA and GSEA revealed that in the high PDGFA group, there was activation of pathways related to inflammation and the immune system. Moreover, analysis of immune infiltration demonstrated a significant association between PDGFA gene expression and the infiltration levels of specific immune cells, including basophils, macrophages M1, macrophages, neutrophils, monocytes, NK cells, and B cells. The involvement of neutrophils in the development and progression of DR is suggested. PDGFA has emerged as a potential marker and is linked to the infiltration of immune cells in DR. These findings shed new light on the underlying mechanisms of DR.

Effects of pulsed electrical stimulation on α-smooth muscle actin and type I collagen expression in human dermal fibroblasts.

Pulsed electrical stimulation (PES) is known to affect cellular activities. We previously found PES to human dermal fibroblasts (HFs) promoted platelet-derived growth factor subunit A (PDGFA) gene expression, which enhanced proliferation. In this study, we investigated PES effects on fibroblast collagen production and differentiation into myofibroblasts. HFs were electrically stimulated at 4800Hz and 5V for 60min. Imatinib, a specific inhibitor of PDGF receptors, was treated before PES. After 6h of PES, PDGFA, α-smooth muscle actin (α-SMA), and collagen type I α1 chain gene expressions were upregulated in PES group. Imatinib suppressed the promoted expression except for PDGFA. Immunofluorescence staining and enzyme-linked immunosorbent assay showed the production of α-SMA and collagen I was enhanced in PES group but suppressed in PES+imatinib group at 48h after PES. Therefore, PES promotes the production of α-SMA and collagen I in fibroblasts, which is triggered by PDGFA that is upregulated early after PES.

Investigation of the Therapeutic Effect of Salbutamol on Endometriosis in a Mouse Model.

Endometriosis is an immune chronic inflammatory disease, and there are currently no more effective drugs for treating endometriosis due to its unknown etiology. Salbutamol is a β2-adrenergic receptor (β2AR) agonist commonly used to treat asthma by selectively activating β2 receptors on airway smooth muscle and leukocytes, exerting bronchial dilation and synergistic anti-inflammatory effects. In recent years, β2AR agonists have been used in endometriosis studies, and we speculate that salbutamol may have a therapeutic effect on endometriosis. The purpose of this research was to explore the therapeutic effect of salbutamol on endometriosis mice. The mouse endometriosis model was established and treated with different doses of salbutamol. Endometrial lesions were harvested for pathological diagnosis, immunohistochemistry (IHC), Masson staining, and toluidine blue analysis. We found that the number and size of endometriotic lesions were all significantly decreased after 3 weeks of treatment with different doses of salbutamol on endometriosis model mice (P < 0.05). After Salbutamol treatment, the amount of mast cells (toluidine blue) and macrophages (F4/80) in the lesions as well as the expressions of interleukin (IL)-1β, tumor necrosis factor (TNF)-ɑ, platelet-derived growth factor subunit B (PDGFB), CD31, transforming growth factor (TGF)-β, Masson staining, BCL2, TUBB3, substance P (SP), and nerve growth factor (NGF) were significantly reduced (P < 0.05). These results suggested that salbutamol could effectively treat endometriosis in mice by reducing immune inflammatory cells and factors, angiogenesis, and fibrosis, increasing apoptosis of endometriotic lesions, and decreasing neurogenesis.

A PDGFRβ-targeting nanodrill system for pancreatic fibrosis therapy

Activated pancreatic stellate cells (PSCs) are the main source of collagen layer deposition and the key target in pancreatic fibrosis. However, no effective treatment specific to pancreatic fibrosis clinically, owing to the drug accumulation blocked by the collagen barrier and thus it is difficult to inhibit activated PSCs precisely. Herein, a PSCs-targeting nano-system based on “nanodrill” strategy (LA-PC) was designed to enhance the accumulation of all-trans retinoic acid (ATRA) in PSCs, relying on the platelet-derived growth factor receptor beta (PDGFRβ)-targeting peptide (pPB: C∗SRNLIDC∗) and collagenase (Col). After being injected into fibrotic mice via tail vein, the Col modified on LA-PC can remove the excess collagen layer, and the drug delivery efficiency through pPB targeting peptide was more than 5 times higher than that of free ATRA, as well as the degree of fibrosis significantly reduced. Notably, this nano-system effectively inhibited platelet-derived growth factor subunit B (PDGF-BB)/PDGFRβ axis on PSCs via a down-regulated extracellular signal-regulated protein kinase (ERK) pathway, and accordingly reduced the level of PDGF-BB. Thus, the smart platform provided a promising strategy for the treatment of pancreatic fibrosis to achieve the precise regulation of PSCs.

Single-cell transcriptomics and chromatin accessibility profiling elucidate the kidney-protective mechanism of mineralocorticoid receptor antagonists.

Mineralocorticoid excess commonly leads to hypertension (HTN) and kidney disease. In our study, we used single-cell expression and chromatin accessibility tools to characterize the mineralocorticoid target genes and cell types. We demonstrated that mineralocorticoid effects were established through open chromatin and target gene expression, primarily in principal and connecting tubule cells and, to a lesser extent, in segments of the distal convoluted tubule cells. We examined the kidney-protective effects of steroidal and nonsteroidal mineralocorticoid antagonists (MRAs), as well as of amiloride, an epithelial sodium channel inhibitor, in a rat model of deoxycorticosterone acetate, unilateral nephrectomy, and high-salt consumption-induced HTN and cardiorenal damage. All antihypertensive therapies protected against cardiorenal damage. However, finerenone was particularly effective in reducing albuminuria and improving gene expression changes in podocytes and proximal tubule cells, even with an equivalent reduction in blood pressure. We noted a strong correlation between the accumulation of injured/profibrotic tubule cells expressing secreted posphoprotein 1 (Spp1), Il34, and platelet-derived growth factor subunit b (Pdgfb) and the degree of fibrosis in rat kidneys. This gene signature also showed a potential for classifying human kidney samples. Our multiomics approach provides fresh insights into the possible mechanisms underlying HTN-associated kidney disease, the target cell types, the protective effects of steroidal and nonsteroidal MRAs, and amiloride.

GIPC1 promotes tumor growth and migration in gastric cancer via activating PDGFR/PI3K/AKT signaling.

The high mortality rate associated with gastric cancer (GC) has resulted in an urgent need to identify novel therapeutic targets for GC. This study aimed to investigate whether GAIP interacting protein, C terminus 1 (GIPC1) represents a therapeutic target and its regulating mechanism in GC. GIPC1 expression was elevated in GC tissues, liver metastasis tissues, and lymph node metastases. GIPC1 knockdown or GIPC1 blocking peptide blocked the platelet-derived growth factor receptor (PDGFR)/PI3K/AKT signaling pathway, and inhibited the proliferation and migration of GC cells. Conversely, GIPC1 overexpression markedly activated the PDGFR/PI3K/AKT signaling pathway, and promoted GC cell proliferation and migration. Furthermore, platelet-derived growth factor subunit BB (PDGF-BB) cytokines and the AKT inhibitor attenuated the effect of differential GIPC1 expression. Moreover, GIPC1 silencing decreased tumor growth and migration in BALB/c nude mice, while GIPC1 overexpression had contrasting effects. Taken together, our findings suggest that GIPC1 functions as an oncogene in GC and plays a central role in regulating cell proliferation and migration via the PDGFR/PI3K/AKT signaling pathway.

Buyang Huanwu Decoction promotes arteriogenesis after hindlimb ischemia in mice by activating PDGF signaling pathway

This study aims to investigate the effect of Buyang Huanwu Decoction on blood flow recovery and arteriogenesis after hindlimb ischemia in mice via the platelet-derived growth factor(PDGF) signaling pathway. Forty C57BL/6 mice were randomized into model(clean water, 10 mL·kg~(-1)·d~(-1)), beraprost sodium(positive control, 18 μg·kg~(-1)·d~(-1)), and low-, medium-, and high-dose(10, 20, and 40 g·kg~(-1)·d~(-1), respectively) Buyang Huanwu Decoction groups(n=8). The hindlimb ischemia model was established by femoral artery ligation. The mice were administrated with corresponding agents by gavage daily for 14 days after ligation. For laser Doppler perfusion imaging, the mice were anesthetized and measured under a Periscan PSI imager. The density of capillary and arterio-le in the ischemic gastrocnemius was measured using immunofluorescence staining of the frozen tissue sections. Western blot was employed to determine the expression of PDGF subunit B(PDGFB), phosphorylated mitogen extracellular kinase(p-MEK), MEK, phosphorylated extracellular signal-regulated kinase(p-ERK), and ERK. Real-time PCR was employed to determine the mRNA level of PDGFB. The Buyang Huanwu Decoction-containing serum was used to treat the vascular smooth muscle cells(VSMCs) in hypoxia at doses of 10% and 20%. The proliferation and migration of VSMCs was assessed in vitro. The results showed that compared with the model group, beraprost sodium and Buyang Huanwu Decoction enhanced the blood flow recovery, increased the capillary and arteriole density, and up-regulated the protein levels of PDGFB, p-MEK, p-ERK, and mRNA levels of PDGFB, with the medium-dose Buyang Huanwu Decoction demonstrating the most significant effect. The 10% Buyang Huanwu Decoction-containing serum enhanced the proliferation and migration of VSMCs. Our findings demonstrate that Buyang Huanwu Decoction up-regulates PDGFB transcription and activates PDGF signaling pathway to promote arteriogenesis and blood flow recovery in ischemic gastrocnemius.

Cross-talk between gastric cancer and hepatic stellate cells promotes invadopodia formation during liver metastasis.

In gastric cancer (GC), the liver is a common organ for distant metastasis, and patients with gastric cancer with liver metastasis (GCLM) generally have poor prognosis. The mechanism of GCLM is unclear. Invadopodia are special membrane protrusions formed by tumor cells that can degrade the basement membrane and ECM. Herein, we investigated the role of invadopodia in GCLM. We found that the levels of invadopodia-associated proteins were significantly higher in liver metastasis than in the primary tumors of patients with GCLM. Furthermore, GC cells could activate hepatic stellate cells (HSCs) within the tumor microenvironment of liver metastases through the secretion of platelet-derived growth factor subunit B (PDGFB). Activated HSCs secreted hepatocyte growth factor (HGF), which activated the MET proto-oncogene, MET receptor of GC cells, thereby promoting invadopodia formation through the PI3K/AKT pathway and subsequently enhancing the invasion and metastasis of GC cells. Therefore, cross-talk between GC cells and HSCs by PDGFB/platelet derived growth factor receptor beta (PDGFRβ) and the HGF/MET axis might represent potential therapeutic targets to treat GCLM.

The effects of treadmill exercise on brain angiogenesis in ovariectomized rats.

Menopause is associated with vascular dysfunction attributed to reduced estrogen levels. Exercise has been proposed to promote angiogenesis and vascular dysfunction. However, studies of brain angiogenesis during menopause are limited. We analyzed the effects of exercise on angiogenesis-related factors in menopausal rat model. Twenty-week-old female Sprague-Dawley rats (N = 18) were randomly divided into a normal control group (N, n = 6), an ovariectomized control group (OVX, n = 6), and an ovariectomy + exercise group (OVX-EX, n = 6). Treadmill exercises were conducted in the OVX-EX group for 8 weeks (15-60 m/min, 1 h/day, and 5 days/week). The current study showed that the expression of angiogenesis-related factors (platelet-derived growth factor subunit A, B, vascular endothelial growth factor, angiopoietin 1, and angiopoietin 2) significantly decreased in the cortex of the OVX group. However, these factors were significantly restored in the cortex of the OVX-EX group after 8 weeks of treadmill exercise. In summary, estrogen deficiency causes vascular dysfunction by inhibiting the expression of angiogenesis-related factors. However, exercise can restore angiogenesis-related factors in OVX rats. Exercise eventually prevents vascular dysfunction in the brain and may help prevent cognitive dysfunction in menopausal women.

Does Nirmatrelvir/Ritonavir Influence the Immune Response against SARS-CoV-2, Independently from Rebound?

Recurrence of coronavirus disease 19 (COVID-19) symptoms and SARS-CoV-2 viral load relapse have been reported in people treated with nirmatrelvir/ritonavir (NM/r). However, little is understood about the etiology of this phenomenon. Our aim was to investigate the relation between the host's immune response and viral rebound. We described three cases of COVID-19 rebound that occurred after treatment with nirmatrelvir/ritonavir (group A). In addition, we compared spike-specific antibody response and plasma cytokine/chemokine patterns of the rebound cases with those of (i) control patients treated with nirmatrelvir/ritonavir who did not show rebound (group B), and (ii) subjects not treated with any anti-SARS-CoV-2 drug (group C). The anti-spike antibodies and plasma cytokines/chemokines were similar in groups A and B. However, we observed a higher anti-BA.2 spike IgG response in patients without antiviral treatment (group C) [geometric mean titer 210,807, 5.1- and 8.2-fold higher compared to group A (p = 0.039) and group B (p = 0.032)]. Moreover, the patients receiving antiviral treatment (groups A-B) showed higher circulating levels of platelet-derived growth factor subunit B (PDGF-BB) and vascular endothelial growth Factors (VEGF) and lower levels of interleukin-9 (IL-9), interleukine-1 receptor antagonist (IL-1 RA), and regulated upon activation normal T cell expressed and presumably secreted chemokine (RANTES) when compared to group C. In conclusion, we observed lower anti-spike IgG levels and different cytokine patterns in nirmatrelvir/ritonavir-treated patients compared to those not treated with anti-SARS-CoV-2 drugs. This suggests that early antiviral treatment, by reducing viral load and antigen presentation, could mitigate the immune response against SARS-CoV-2. The clinical relevance of such observation should be further investigated in larger populations.

Research Note: Transcriptome analysis reveals differentially expressed genes regulated muscle development in Pekin ducks during dietary threonine deficiency

To investigate the underlying molecular mechanism of threonine (Thr) regulation on the development of breast muscle in Pekin ducks, 240 male Pekin ducks at 1 d of age were fed a Thr deficiency diet (Thr-D), Thr sufficiency diet (Thr-S), or Thr excess diet (Thr-E) for 21 d. The results showed that Thr-D reduced body weight (BW), average weight gain (ADG), and average feed intake (ADFI), and increased the feed/gain (F/G) in Pekin ducks (P < 0.05), and Thr-E did not affect BW, ADG, ADFI, or F/G (P > 0.05), compared with Thr-S. The diameter and cross-sectional area of the breast muscle fibers in the Thr-S group were larger than those in the Thr-D group (P < 0.05). RNA sequencing revealed 1,300 differential expressed genes (DEGs) between the Thr-D and Thr-S groups, of which 625 were upregulated and 675 were downregulated by Thr-D. KEGG analysis showed that the upregulated genes were enriched in mTOR, FoxO, Wnt, fat digestion and absorption, and other signaling pathways. The downregulated genes were enriched in the MAPK signaling, glycolysis/gluconeogenesis, adipocytokine signaling, and biosynthesis of unsaturated fatty acids signaling pathways. The genes of Wnt family member 3a (Wnt3a), myogenin, myozenin 2, and insulin like growth factor 2 mRNA binding protein were upregulated, and platelet derived growth factor subunit B, PDGF receptor beta and Wnt4 were downregulated by Thr deficiency, which involving in muscle development. Our findings indicated that Thr increased breast fiber size, perhaps because Thr affected the proliferation and differentiation of satellite cells in breast muscle of ducks after hatch. Our results provide novel insights into new understanding of the molecular mechanisms underlying breast muscle development in ducks subjected to dietary Thr.

Isolation and Biological Evaluation of Alfa-Mangostin as Potential Therapeutic Agents against Liver Fibrosis.

The increased proliferation and activation of hepatic stellate cells (HSCs) are associated with liver fibrosis development. To date, there are no FDA-approved drugs for the treatment of liver cirrhosis. Augmentation of HSCs apoptosis is one of the resolutions for liver fibrosis. In this study, we extracted α-mangostin (1,3,6-trihydroxy-7-methoxy-2,8-bis(3-methyl-2-butenyl)-9H-xanthen-9-one) from the fruit waste components of mangosteen pericarp. The isolated α-mangostin structure was determined and characterized with nuclear magnetic resonance (NMR) and high-resolution mass spectrometry (HRMS) and compared with those known compounds. The intracellular signaling pathway activities of α-mangostin on Transforming growth factors-beta 1 (TGF-β1) or Platelet-derived growth factor subunit B (PDGF-BB) induced HSCs activation and were analyzed via Western blot and Real-time Quantitative Polymerase Chain Reaction (Q-PCR). α-Mangostin-induced mitochondrial dysfunction and apoptosis in HSCs were measured by seahorse assay and caspase-dependent cleavage. The in vivo anti-fibrotic effect of α-mangostin was assessed by carbon tetrachloride (CCl4) treatment mouse model. The data showed that α-mangostin treatment inhibited TGF-β1-induced Smad2/3 phosphorylation and alpha-smooth muscle actin (α-SMA) expression in HSCs in a dose-dependent manner. Regarding the PDGF-BB-induced HSCs proliferation signaling pathways, α-mangostin pretreatment suppressed the phosphorylation of extracellular-signal-regulated kinase (ERK) and p38. The activation of caspase-dependent apoptosis and dysfunction of mitochondrial respiration (such as oxygen consumption rate, ATP production, and maximal respiratory capacity) were observed in α-mangostin-treated HSCs. The CCl4-induced liver fibrosis mouse model showed that the administration of α-mangostin significantly decreased the expression of the fibrosis markers (α-SMA, collagen-a2 (col1a2), desmin and matrix metalloproteinase-2 (MMP-2)) as well as attenuated hepatic collagen deposition and liver damage. In conclusion, this study demonstrates that α-mangostin attenuates the progression of liver fibrosis through inhibiting the proliferation of HSCs and triggering apoptosis signals. Thus, α-mangostin may be used as a potential novel therapeutic agent against liver fibrosis.