MicroRNA-29b inhibits TGF-β1-induced fibrosis via regulation of the TGF-β1/Smad pathway in primary human endometrial stromal cells

Thyroid dysfunction in Hashimoto's thyroiditis: a pilot study on the putative role of miR-29a and TGFβ1

PURPOSE

Hashimoto's thyroiditis (HT) is one of the most common causes of thyroid dysfunction in iodine sufficient worldwide areas, but its molecular mechanisms are not completely understood. To this regard, this study aimed to assess serum levels of miRNA-29a (miR-29a) and transforming growth factor beta 1 (TGFβ1) in HT patients with different patterns of thyroid function.

METHODS

A total of 29 HT patients, with a median age of 52 years (21-68) were included. Of these, 13 had normal thyroid function (Eu-HT); 8 had non-treated hypothyroidism (Hypo-HT); 8 had hypothyroidism on replacement therapy with LT4 (subst-HT). All patients had serum miR-29a assayed through qRT-PCR and serum TGFβ1 assayed by ELISA.

RESULTS

Serum miR-29a levels were significantly down-regulated in patients with Hypo-HT compared to Eu-HT patients (P < 0.01) and subst-HT patients (P < 0.05). A significant negative correlation was detected between serum miR-29a levels and TSH levels (r = -0.60, P < 0.01). Serum TGFβ1 levels were significantly higher in Hypo-HT than both Eu-HT (P < 0.01) and subst-HT patients (P < 0.05). A negative correlation was observed between serum miR-29a and TGFβ1 (r = -0.75, P < 0.01).

CONCLUSIONS

In conclusion, Hypo-HT patients had lower levels of serum miR-29a and higher levels of TGFβ1 in comparison with Eu-HT patients. Worthy of note, subst-HT patients showed restored serum miR-29a levels compared with Hypo-HT group, associated with lower serum TGFβ1. These novel findings may suggest a possible impact of replacement therapy with levothyroxine on serum miR-29a levels in HT.

Evolution of biotechnological advances and regenerative therapies for endometrial disorders: a systematic review

BACKGROUND

The establishment and maintenance of pregnancy depend on endometrial competence. Asherman syndrome (AS) and intrauterine adhesions (IUA), or endometrial atrophy (EA) and thin endometrium (TE), can either originate autonomously or arise as a result from conditions (i.e. endometritis or congenital hypoplasia), or medical interventions (e.g. surgeries, hormonal therapies, uterine curettage or radiotherapy). Affected patients may present an altered or inadequate endometrial lining that hinders embryo implantation and increases the risk of poor pregnancy outcomes and miscarriage. In humans, AS/IUA and EA/TE are mainly treated with surgeries or pharmacotherapy, however the reported efficacy of these therapeutic approaches remains unclear. Thus, novel regenerative techniques utilizing stem cells, growth factors, or tissue engineering have emerged to improve reproductive outcomes.

OBJECTIVE AND RATIONALE

This review comprehensively summarizes the methodologies and outcomes of emerging biotechnologies (cellular, acellular, and bioengineering approaches) to treat human endometrial pathologies. Regenerative therapies derived from human tissues or blood which were studied in preclinical models (in vitro and in vivo) and clinical trials are discussed.

SEARCH METHODS

A systematic search of full-text articles available in PubMed and Embase was conducted to identify original peer-reviewed studies published in English between January 2000 and September 2023. The search terms included: human, uterus, endometrium, Asherman syndrome, intrauterine adhesions, endometrial atrophy, thin endometrium, endometritis, congenital hypoplasia, curettage, radiotherapy, regenerative therapy, bioengineering, stem cells, vesicles, platelet-rich plasma, biomaterials, microfluidic, bioprinting, organoids, hydrogel, scaffold, sheet, miRNA, sildenafil, nitroglycerine, aspirin, growth hormone, progesterone, and estrogen. Preclinical and clinical studies on cellular, acellular, and bioengineering strategies to repair or regenerate the human endometrium were included. Additional studies were identified through manual searches.

OUTCOMES

From a total of 4366 records identified, 164 studies (3.8%) were included for systematic review. Due to heterogeneity in the study design and measured outcome parameters in both preclinical and clinical studies, the findings were evaluated qualitatively and quantitatively without meta-analysis. Groups using stem cell-based treatments for endometrial pathologies commonly employed mesenchymal stem cells (MSCs) derived from the human bone marrow or umbilical cord. Alternatively, acellular therapies based on platelet-rich plasma (PRP) or extracellular vesicles are gaining popularity. These are accompanied by the emergence of bioengineering strategies based on extracellular matrix (ECM)-derived hydrogels or synthetic biosimilars that sustain local delivery of cells and growth factors, reporting promising results. Combined therapies that target multiple aspects of tissue repair and regeneration remain in preclinical testing but have shown translational value. This review highlights the myriad of therapeutic material sources, administration methods, and carriers that have been tested.

WIDER IMPLICATIONS

Therapies that promote endometrial proliferation, vascular development, and tissue repair may help restore endometrial function and, ultimately, fertility. Based on the existing evidence, cost, accessibility, and availability of the therapies, we propose the development of triple-hit regenerative strategies, potentially combining high-yield MSCs (e.g. from bone marrow or umbilical cord) with acellular treatments (PRP), possibly integrated in ECM hydrogels. Advances in biotechnologies together with insights from preclinical models will pave the way for developing personalized treatment regimens for patients with infertility-causing endometrial disorders such as AS/IUA, EA/TE, and endometritis.

REGISTRATION NUMBER

https://osf.io/th8yf/.

LncRNA MALAT1 Knockdown Alleviates Fibrogenic Response in Human Endometrial Stromal Cells Via the miR-22-3p/TGFβR1/Smad2/3 Pathway

Intrauterine adhesion (IUA) resulting from irreversible fibrotic repair of endometrium is the main cause of secondary infertility in women, and current therapeutic approaches to IUA are limited. Increasing evidence has suggested the important role of competitive endogenous RNA (ceRNA) in IUA pathologies. This study aimed to investigate the long noncoding RNA (lncRNA) metastasis associated lung adenocarcinoma transcript 1 (MALAT1)-associated ceRNA in IUA development. We harvested endometrial tissues from patients with or without IUA and extracted endometrial stromal cells (ESCs) from normal endometrial tissues. Transforming growth factor β1 (TGF-β1) was used to induce fibrosis in ESCs. The expression of transforming growth factor β receptor 1 (TGFβR1), α-smooth muscle actin, phosphorylated suppressor of mother against decapentaplegic (p-Smad)2/3, collagen type I alpha 1, MALAT1, and microRNA (miR)-22-3p in endometrial tissues and ESCs was measured by reverse transcription quantitative polymerase chain reaction (RT-qPCR) or western blotting. Pearson's correlation analysis was conducted to assess the correlation between miR-22-3p expression or TGFβR1 and MALAT1 expression in endometrial tissues. The expression of TGFβR1 in ESCs was also evaluated by immunofluorescence staining. The location of MALAT1 was examined by fluorescence in situ hybridization. Luciferase reporter assays were performed to verify the binding relationship between MALAT1 or TGFβR1 and miR-22-3p. Cell viability was assessed via cell counting kit-8 assays. Our findings revealed that lncRNA MALAT1 and TGFβR1 were upregulated while miR-22-3p was downregulated in IUA endometrial tissues or TGF-β1-stimulated ESCs, and lncRNA MALAT1 expression was negatively correlated with miR-22-3p expression while being positively correlated with TGFβR1 expression in IUA endometrial tissues. Additionally, lncRNA MALAT1 was mainly located in the cytoplasm of ESCs and directly targeted miR-22-3p to regulate TGFβR1 expression. Moreover, knockdown of lncRNA MALAT1 exerted anti-fibrotic effects on ESCs by targeting miR-22-3p, and miR-22-3p overexpression inhibited the fibrosis of ESCs by binding to TGFβR1 3'untranslated region. Collectively, lncRNA MALAT1 promotes endometrial fibrosis by sponging miR-22-3p to regulate TGFβR1 and Smad2/3, and inhibition of MALAT1 may represent a promising therapeutic option for suppressing endometrial fibrosis.

Roles and Mechanisms of miRNAs in Abdominal Aortic Aneurysm: Signaling Pathways and Clinical Insights

PURPOSE OF REVIEW

Abdominal aortic aneurysm refers to a serious medical condition that can cause the irreversible expansion of the abdominal aorta, which can lead to ruptures that are associated with up to 80% mortality. Currently, surgical and interventional procedures are the only treatment options available for treating abdominal aortic aneurysm patients. In this review, we focus on the upstream and downstream molecules of the microRNA-related signaling pathways and discuss the roles, mechanisms, and targets of microRNAs in abdominal aortic aneurysm modulation to provide novel insights for precise and targeted drug therapy for the vast number of abdominal aortic aneurysm patients.

RECENT FINDINGS

Recent studies have highlighted that microRNAs, which are emerging as novel regulators of gene expression, are involved in the biological activities of regulating abdominal aortic aneurysms. Accumulating studies suggested that microRNAs modulate abdominal aortic aneurysm development through various signaling pathways that are yet to be comprehensively summarized. A total of six signaling pathways (NF-κB signaling pathway, PI3K/AKT signaling pathway, MAPK signaling pathway, TGF-β signaling pathway, Wnt signaling pathway, and P53/P21 signaling pathway), and a total of 19 miRNAs are intimately associated with the biological properties of abdominal aortic aneurysm through targeting various essential molecules. MicroRNAs modulate the formation, progression, and rupture of abdominal aortic aneurysm by regulating smooth muscle cell proliferation and phenotype change, vascular inflammation and endothelium function, and extracellular matrix remodeling. Because of the broad crosstalk among signaling pathways, a comprehensive analysis of miRNA-mediated signaling pathways is necessary to construct a well-rounded upstream and downstream regulatory network for future basic and clinical research of AAA therapy.

MicroRNA-29b attenuates fibrosis in a rat model of Peyronie's disease

BACKGROUND

Peyronie's disease is characterized by the formation of fibrotic plaques in the penile tunica albuginea. Effective treatments are limited, warranting the investigation of new promising therapies, such as the application of microRNAs that regulate fibrosis-related genes.

OBJECTIVE

We aimed to investigate the therapeutic potential of mimicking microRNA-29b in a fibrin-induced rat model of Peyronie's disease.

MATERIAL/METHODS

The study was designed in two phases. To establish an optimal Peyronie's disease model, rats received either human fibrin and thrombin or saline solutions into the tunica albuginea on days 0 and 5. The animal model validation was done through expression and histopathological analyses, the latest by an experienced uropathologist. After validation, we performed microRNA-29b treatment on days 14, 21, and 28 of the study. This phase had control (normal saline) and scramble (microRNA scramble) groups. The mid-penile shaft was removed on day 30 for histological examination and molecular analyses in both study stages.

RESULTS

The control group displayed typical tunica albuginea histologic architecture in the animal model validation. In Peyronie's disease group, the Hematoxylin and eosin and Masson Trichrome staining methods demonstrated an interstitial inflammatory process with concomitant dense fibrotic plaques as well as disarrangement of collagen fibers. Additionally, we found out that reduced microRNA-29b (p = 0.05) was associated with significantly increased COL1A1 and transforming growth factor β1 genes and proteins (p > 0.05) in the Peyronie's disease group. After treatment with mimic microRNA-29b stimulation, the Hematoxylin & eosin and Masson Trichrome staining revealed a discrete and less dense fibrotic plaque. This result was associated with significantly decreasing expression of COL1A1, COL3A1, and transforming growth factor β1 genes and proteins (p < 0.05).

DISCUSSION

The fibrin-induced animal model showed significant histopathological and molecular changes compared to the Control group, suggesting that our model was appropriate. Previous findings have shown that increased expression of microRNA-29b was associated with decreased pathological fibrosis. In the present study, treatment with microRNA-29b decreased the gene and protein expression of collagens and transforming growth factor β1. This study reveals the therapeutic potential for Peyronie's disease involving molecular targets.

CONCLUSION

MicroRNA-29b application on the rat's tunica albuginea attenuated fibrosis, arising as a novel potential strategy for Peyronie's disease management.

Crosstalk among miR-29, α-SMA, and TGFβ1/β3 in melatonin-induced exosome (Mel-prExo) treated human limbal mesenchymal stem cells (hLMSCs): An insight into scarless healing of the cornea

Inflammatory mediators that infiltrate the corneal stroma after corneal infections, trauma or refractive surgery can trigger the transformation of corneal keratocytes into myofibroblasts, resulting in highly irregular collagen deposition and subsequently corneal scarring. Mesenchymal stem cells (MSCs) can be used as therapeutic agents to regenerate corneal and conjunctival tissue damage, regulate inflammation, and reduce the development of limbal stem cell failure. The use of MSC-derived exosomes as a cell-free therapeutic vector is a novel therapeutic approach. This study aimed to assess the effect of exosomes obtained from melatonin (Mel)-treated human limbal mesenchymal stem cells (hLMSCs) on naïve hLMSCs and to determine their influence on the antifibrotic and pro-regenerative pathways involved in corneal scarring. hLMSCs were treated with varying concentrations of Mel, followed by isolation and characterization of the procured exosomes (Mel-prExos). These exosomes were added to the cell culture media of naïve hLMSCs to examine their antifibrotic and pro-regenerative effects. The expression of miR-155, miR-29, TGFβ1, TGFβ3, PPARγ, and α-SMA miRNAs and genes were compared between Mel-treated hLMSCs and Mel-prExo-treated hLMSCs by using real-time PCR. We found that at 1 μM Mel and in the presence of Mel-prExos, TGFβ1 was expressed 0.001-fold, while TGFβ3 was expressed 0.6-fold. miR-29 expression was increased 38-fold in the control-Exo group compared to that in the control group. Changes in TGFβ1/β3 and α-SMA expression are associated with miR-29 and miR-155. This approach could prove beneficial for ocular surface tissue engineering applications.

Predictive Value of Serum microRNA-29b-3p in Recurrence of Atrial Fibrillation After Radiofrequency Catheter Ablation

Objective

Atrial fibrillation (AF) is a common arrhythmia. This study explored serum miR-29b-3p expression in AF patients and its value in predicting AF recurrence after radiofrequency catheter ablation (RFCA).

Methods

Totally 100 AF patients who underwent RFCA were enrolled, with 100 individuals without AF as controls. Serum miR-29b-3p expression in participants was determined using RT-qPCR. The correlation between miR-29b-3p and atrial fibrosis markers (FGF-21/FGF-23) was assessed by Pearson analysis. The diagnostic efficacy of serum miR-29b-3p and FGF-21/FGF-23 in predicting AF recurrence after RFCA was analyzed by the receiver operating characteristic (ROC) curves. The Kaplan-Meier method was adopted to evaluate the effect of miR-29b-3p expression on the incidence of AF recurrence after RFCA. The independent risk factors for AF recurrence after RFCA were analyzed by logistic regression analysis.

Results

Serum miR-29b-3p was poorly expressed in AF patients. After RFCA, AF patients showed elevated serum miR-29b-3p expression. Serum miR-29b-3p expression in AF patients negatively correlated with serum FGF-21 and FGF-23 concentrations. The cut-off values of serum miR-29b-3p, FGF-21, and FGF-23 in identifying AF recurrence were 0.860 (sensitivity: 100.00%, specificity: 39.71%), 222.2 pg/mL (sensitivity: 96.88%, specificity: 32.35%) and 216.3 ng/mL (sensitivity: 53.13%, specificity: 70.59%), respectively. Patients with low miR-29b-3p expression had a significantly higher incidence of AF recurrence than patients with high miR-29b-3p expression. Serum miR-29b-3p expression was one of the independent risk factors for AF recurrence after RFCA.

Conclusion

Low miR-29b-3p expression in AF patients has certain predictive values and is one of the independent risk factors for AF recurrence after RFCA.

Umbilical cord mesenchymal stem cell-derived exosomes inhibits fibrosis in human endometrial stromal cells via miR-140-3p/FOXP1/Smad axis

Endometrial fibrosis is the histologic appearance of intrauterine adhesion (IUA). Emerging evidences demonstrated umbilical cord mesenchymal stem cell-derived exosomes (UCMSC-exo) could alleviate endometrial fibrosis. But the specific mechanism is not clear. In this study, we explored the effect of UCMSC-exo on endometrial fibrosis, and investigated the possible role of miR-140-3p/FOXP1/Smad axis in anti-fibrotic properties of UCMSC-exo. UCMSC-exo were isolated and identified. Transforming growth factor-β (TGF-β) was used to induce human endometrial stromal cell (HESC) fibrosis. Dual luciferase assay was performed to verify the relationship between miR-140-3p and FOXP1. The expressions of fibrotic markers, SIP1, and p-Smad2/p-Smad3 in HESCs stimulated with UCMSC-exo were detected by western blot. In addition, the effects of miR-140-3p mimic, miR-140-3p inhibitor and FOXP1 over-expression on endometrial fibrosis were assessed. The isolated UCMSC-exo had a typical cup-shaped morphology and could be internalized into HESCs. The expressions of fibrotic markers were significantly increased by TGF-β, which was reversed by UCMSC-exo. MiR-140-3p in UCMSC-exo ameliorated TGf-β-induced HESCs fibrosis. FOXP1 was identified as the direct target of miR-140-3p, which could inversely regulate miR-140-3p's function on HESCs fibrosis. Furthermore, we demonstrated that miR-140-3p in UCMSC-exo regulated Smad signal pathway to exert the anti-fibrotic effect in HESCs. The anti-fibrotic effect of UCMSC-derived exosomes against HESC fibrosis was at least partially achieved by miR-140-3p/FOXP1/Smad axis.

17β-Estradiol mediates TGFBR3/Smad2/3 signaling to attenuate the fibrosis of TGF-β1-induced bovine endometrial epithelial cells via GPER

Abnormal function and fibrosis of endometrium caused by cows' endometritis pose difficult implantation of embryos and uterine cavity adhesions. 17β-Estradiol (E2) serves as the most effective aromatized estrogen, and its synthetase and receptors have been detected in the endometrium. Studies have demonstrated the positive role of estrogen in combating pathological fibrosis in diverse diseases. However, it is still unknown whether E2 regulates endometrium fibrosis in bovine endometritis. Herein, we evaluated the expression patterns of transforming growth factor-β1 (TGF-β1), epithelial-mesenchymal transformation (EMT)-related proteins (α-SMA, vimentin N-cadherin and E-cadherin), cytochrome P450 19A1 (CYP19A1), and G protein-coupled estrogen receptor (GPER) in bovine healthy endometrium and Inflammatory endometrium. Our data showed that the inflamed endometrium presented low CYP19A1 and GPER expression, and significantly higher EMT process versus the normal tissue. Moreover, we established a TGF-β1-induced fibrosis model in BEND cells, and found that E2 inhibited the EMT process of BEND cells in a dose-dependent manner. The anti-fibrotic effect of E2 was blocked by the GPER inhibitor G15, but not the estrogen nuclear receptors (ERs) inhibitor ICI182780. Moreover, the GPER agonist G1 inhibited fibrosis and Smad2/3 phosphorylation but increased the expression of TGFBR3 in BEND cells. Transfection with TGFBR3 small interfering RNA blocked the effect of G1 on fibrosis of BEND cells and upregulated the expression of P-Smad2/3. Our in vivo data also showed that E2 and G1 affected uterus fibrosis in mice endometritis model caused by LPS, which was associated with the inhibition of TGFBR3/Smad2/3 signaling. In conclusion, our data implied that E2 alleviates the fibrosis of TGF-β1-induced BEND cells, which is associated with the GPER mediation of TGFBR3/Smad2/3 signaling.

miR-200a-3p regulates epithelial-mesenchymal transition and inflammation in chronic rhinosinusitis with nasal polyps by targeting ZEB1 via ERK/p38 pathway

BACKGROUND

Several biological processes are regulated by miR-200a-3p, including cell proliferation, migration, and epithelial-mesenchymal transition (EMT). In this study we aimed to uncover the diagnostic value and molecular mechanisms of miR-200a-3p in chronic rhinosinusitis with nasal polyps (CRSwNP).

METHODS

The expressions of miR-200a-3p were detected by quantitative real-time polymerase chain reaction (qRT-PCR), Zinc finger E-box binding homeobox 1 (ZEB1) levels were examined by qRT-PCR and immunofluorescence staining. The interaction between miR-200a-3p and ZEB1 was predicted by TargetScan Human 8.0 and confirmed by dual-luciferase reporter assays. In addition, the effect of miR-200a-3p and ZEB1 on EMT-related makers and inflammation cytokines was assessed by qRT-PCR and Western blotting in human nasal epithelial cells (hNEpCs) and primary human nasal mucosal epithelial cells (hNECs).

RESULTS

We found that miR-200a-3p was downregulated in non-eosinophilic and eosinophilic CRSwNP patients when compared with controls. The diagnostic value of miR-200a-3p in serum is reflected by the receiver operating characteristic curve and the 22-item Sino-Nasal Outcome Test. Bioinformatic analysis and luciferase reporter assay identified ZEB1 as a target of miR-200a-3p. ZEB1 was more highly expressed in CRSwNP than in controls. Furthermore, miR-200a-3p inhibitor or ZEB1 overexpression significantly suppressed the epithelial marker E-cadherin; promoted the activation of vimentin, α-spinal muscle atrophy, and N-cadherin; and aggravated inflammation in hNEpCs. Knockdown of ZEB1 significantly alleviated the cellular remodeling caused by miR-200a-3p inhibitor via the extracellular signal-regulated kinase (ERK)/p38 pathway in hNECs.

CONCLUSIONS

miR-200a-3p suppresses EMT and inflammation by regulating the expression of ZEB1 via the ERK/p38 pathway. Our study presents new ideas for protecting nasal epithelial cells from tissue remodeling and finding a possible target for disease.

TNFα-Induced Altered miRNA Expression Links to NF-κB Signaling Pathway in Endometriosis

Endometriosis is a common gynecological inflammatory disorder characterized by immune system dysregulation, which is involved in lesion initiation and progression. Studies have demonstrated that several cytokines are associated with the evolution of endometriosis, including tumor necrosis factor-α (TNFα). TNFα is a non-glycosylated cytokine protein with potent inflammatory, cytotoxic, and angiogenic potential. In the current study, we examined the ability of TNFα to induce dysregulation of microRNAs (miRNAs) linked to NFkB signaling pathways, thus contributing to the pathogenesis of endometriosis. Using RT-qPCR, the expression of several miRNAs was quantified in primary cells derived from eutopic endometrium of endometriosis subjects (EESC) and normal endometrial stromal cells (NESC), and also TNFα-treated NESCs. The phosphorylation of the pro-inflammatory molecule NF-κB and the candidates of the survival pathways PI3K, AKT, and ERK was measured by western blot analysis. The elevated secretion of TNFα in EESCs downregulates the expression level of several miRNAs significantly in EESCs compared to NESCs. Also, treatment of NESCs with exogenous TNFα significantly reduced the expression of miRNAs in a dose-dependent manner to levels similar to EESCs. In addition, TNFα significantly increased the phosphorylation of the PI3K, AKT, ERK, and NF-κB signaling pathways. Notably, treatment with curcumin (CUR, diferuloylmethane), an anti-inflammatory polyphenol, significantly increased the expression of dysregulated miRNAs in EESC in a dose-dependent manner. Our findings demonstrate that TNFα is upregulated in EESCs, which subsequently dysregulates the expression of miRNAs, contributing to the pathophysiology of endometriotic cells. CUR effectively inhibits the expression of TNFα, subsequently altering miRNA levels and suppressing the phosphorylation of AKT, ERK, and NF-κB.

lncRNA TUG1 as potential novel biomarker for prognosis of cardiovascular diseases

Globally, cardiovascular diseases (CVDs) are among the leading causes of death. In light of the high prevalence and mortality of CVDs, it is imperative to understand the molecules involved in CVD pathogenesis and the signaling pathways that they initiate. This may facilitate the development of more precise and expedient diagnostic techniques, the identification of more effective prognostic molecules and the identification of potential therapeutic targets. Numerous studies have examined the role of lncRNAs, such as TUG1, in CVD pathogenesis in recent years. According to this review article, TUG1 can be considered a biomarker for predicting the prognosis of CVD.

MicroRNA-29a Mitigates Laminectomy-Induced Spinal Epidural Fibrosis and Gait Dysregulation by Repressing TGF-β1 and IL-6

Spinal epidural fibrosis is one of the typical features attributable to failed back surgery syndrome, with excessive scar development in the dura and nerve roots. The microRNA-29 family (miR-29s) has been found to act as a fibrogenesis-inhibitory factor that reduces fibrotic matrix overproduction in various tissues. However, the mechanistic basis of miRNA-29a underlying the overabundant fibrotic matrix synthesis in spinal epidural scars post-laminectomy remained elusive. This study revealed that miR-29a attenuated lumbar laminectomy-induced fibrogenic activity, and epidural fibrotic matrix formation was significantly lessened in the transgenic mice (miR-29aTg) as compared with wild-type mice (WT). Moreover, miR-29aTg limits laminectomy-induced damage and has also been demonstrated to detect walking patterns, footprint distribution, and moving activity. Immunohistochemistry staining of epidural tissue showed that miR-29aTg was a remarkably weak signal of IL-6, TGF-β1, and DNA methyltransferase marker, Dnmt3b, compared to the wild-type mice. Taken together, these results have further strengthened the evidence that miR-29a epigenetic regulation reduces fibrotic matrix formation and spinal epidural fibrotic activity in surgery scars to preserve the integrity of the spinal cord core. This study elucidates and highlights the molecular mechanisms that reduce the incidence of spinal epidural fibrosis, eliminating the risk of gait abnormalities and pain associated with laminectomy.

Effect of stem cell conditional medium-loading adhesive hydrogel on TGF-β1-induced endometrial stromal cell fibrosis

Introduction: Uterine adhesion (IUA) is a severe complication that results from uterine operations or uterine infections. Hysteroscopy is considered the gold standard for the diagnosis and treatment of uterine adhesions. Yet, this invasive procedure leads to re-adhesions after hysteroscopic treatment. Hydrogels loading functional additives (e.g., placental mesenchymal stem cells (PC-MSCs)) that can act as physical barriers and promote endometrium regeneration are a good solution. However, traditional hydrogels lack tissue adhesion which makes them unstable under a rapid turnover of the uterus, and PC-MSCs have biosafety risks when used as functional additives. Methods: In this study, we coupled an adhesive hydrogel with a PC-MSCs conditioned medium (CM) to form a hybrid of gel and functional additives (CM/Gel-MA). Results and Discussion: Our experiments show that CM/Gel-MA enhances the activity of endometrial stromal cells (ESCs), promotes cell proliferation, and reduces the expression of α-SMA, collagen I, CTGF, E-cadherin, and IL-6, which helps to reduce the inflammatory response and inhibit fibrosis. We conclude that CM/Gel-MA can more potentially prevent IUA by combining the physical barriers from adhesive hydrogel and functional promotion from CM.

TNFα-induced altered miRNA expression links to NF-κB signaling pathway in endometriosis

Endometriosis is a common gynecological inflammatory disorder characterized by immune system dysregulation, which is involved in lesion initiation and progression. Studies have demonstrated that several cytokines are associated with the evolution of endometriosis, including tumor necrosis factor-α (TNFα). TNFα is a non-glycosylated cytokine protein with potent inflammatory, cytotoxic, and angiogenic potential. In the current study, we examined the ability of TNFα to induce dysregulation of microRNAs (miRNAs) linked to NFkB-signaling pathways, thus contributing to the pathogenesis of endometriosis. Using RT-QPCR, the expression of several miRNAs were quantified in primary cells derived from eutopic endometrium of endometriosis subjects (EESC) and normal endometrial stromal cells (NESC) and also TNFα treated NESCs. The phosphorylation of the pro-inflammatory molecule NF-κB and the candidates of the survival pathways PI3K, AKT and ERK was measured by westernblot analysis. The elevated secretion of TNFα in EESCs downregulates the expression level of several miRNAs significantly (p < 0.05) in EESCs compared to NESC. Also treatment of NESCs with exogenous TNFα significantly reduced the expression of miRNAs in a dose-dependent manner to levels similar to EESCs. In addition, TNFα significantly increased the phosphorylation of the PI3K, AKT, ERK, and NF-κB signaling pathways. Notably, treatment with curcumin (CUR, diferuloylmethane), an anti-inflammatory polyphenol, significantly increased the expression of dysregulated miRNAs in EESC in a dose-dependent manner. Our findings demonstrate that TNFα is upregulated in EESCs, which subsequently dysregulates the expression of miRNAs, contributing to the pathophysiology of endometriotic cells. CUR effectively inhibits the expression of TNFα, subsequently altering miRNA levels and suppresses the phosphorylation of AKT, ERK, and NF-κB.

Exosome-Based Regimen Rescues Endometrial Fibrosis in Intrauterine Adhesions Via Targeting Clinical Fibrosis Biomarkers

Intrauterine adhesions (IUA), which is characterized by endometrial fibrosis, continue to be the most common cause of uterine infertility globally. Our work revealed that 3 fibrotic progression markers (Vimentin, COL5A2, and COL1A1) were significantly increased in the endometrium of IUA patients. Mesenchymal stem cell-derived exosomes (EXOs) have been recently revealed as a cell-free therapy for fibrosis diseases. Nevertheless, the application of EXOs is restricted by the short residency duration in the target tissue. To overcome this limitation, herein, we reported an exosome-based regimen (EXOs-HP) that thermosensitive poloxamer hydrogel possessed the ability to efficiently promote the residency duration of EXOs in the uterine cavity. By downregulating fibrotic progression markers (Vimentin, COL5A2, and COL1A1), EXOs-HP could significantly restore the function and structure of the injured endometrium in the IUA model. Our work provides the theoretical and experimental foundation of EXOs-HP in treating IUA, highlighting the clinical potential of topical EXOs-HP delivery system in IUA patients.

CircRNA_0263 and circRNA_1507 are dysregulated in a rat model of atrial fibrosis induced by chronic intermittent hypoxia

Aims: This study aimed to characterize circular RNA (circRNA) profiles associated with atrial fibrosis-related atrial fibrillation (AF) and reveal critical circRNAs for AF. Methods: Sprague Dawley rats were randomly divided into control and atrial fibrosis-related AF groups (n = 15 in each group). The rats in the atrial fibrosis-related AF group were induced by chronic intermittent hypoxia (CIH), and then confirmed by electrocardiograms, echocardiography, hematoxylin-eosin staining, Masson staining, immunohistochemistry assays and western blotting. After that, the atrial tissues were sent for circRNA sequencing, and the differentially expressed circRNAs were identified and validated by quantitative real-time polymerase chain reaction (qRT-PCR). Finally, a series of cell experiments were performed to explore the roles of two crucial circRNAs in rat atrial fibroblasts. Results: A CIH-induced AF model was successfully established in the rats. After sequencing, five upregulated and 11 downregulated circRNAs were identified in the CIH-induced AF group. These dysregulated circRNAs were primarily associated with "carbohydrate metabolism" and "cardiovascular diseases". Two circRNAs (circRNA_0263 and circRNA_1507) were predicted to regulate target gene expression by interacting with corresponding miRNAs, including rno-miR-29b-5p, rno-miR-29b-3p, rno-miR-496-5p, rno-miR-136-5p, and novel123-mature. Additionally, circRNA_0263 knockdown and circRNA_1507 overexpression inhibited the cell viability of fibroblasts, and downregulated the expression of fibrosis-related proteins. Conclusion: A series of circRNAs were identified as dysregulated in an AF rat model, and circRNA_0263 and circRNA_1507 might be crucial for atrial fibrosis-related AF development by competing with several miRNAs.

Telocyte-Derived Exosomes Provide an Important Source of Wnts That Inhibits Fibrosis and Supports Regeneration and Repair of Endometrium

Intrauterine adhesions (IUAs) often occurred after common obstetrical and gynecological procedures or infections in women of reproductive age. It was characterized by the formation of endometrial fibrosis and prevention of endometrial regeneration, usually with devastating fertility consequences and poor treatment outcomes so far. Telocytes (TCs), as a novel interstitial cell type, present in female uterus with in vitro therapeutic potential in decidualization-defective gynecologic diseases. This study aims to further investigate the role of TC-derived Wnt ligands carried by exosomes (Exo) in reversal of fibrosis and enhancement of regeneration repair in endometrium. IUA cellular and animal models were established from endometrial stromal cells (ESCs) and mice, followed with treatment of TC-conditioned medium (TCM) or TC-derived Exo. In cellular model, fibrosis markers (collagen type 1 alpha 1 [COL1A1], fibronectin [FN], and α-smooth muscle actin [α-SMA]), angiogenesis (vascular endothelial growth factor [VEGF]), and pathway protein (β-catenin) were determined by quantitative reverse transcription polymerase chain reaction (qRT-PCR), Western blotting (WB), and immunofluorescence. Results showed that, TCs (either TCM or TC-derived Exo) provide a source of Wnts that inhibit cellular fibrosis, as evidenced by significantly elevated VEGF and β-catenin with decreased fibrotic markers, whereas TCs lost salvage on fibrosis after being blocked with Wnt/β-catenin inhibitors (XAV939 or ETC-159). Further in mouse model, regeneration repair (endometrial thickness, number of glands, and fibrosis area ratio), fibrosis markers (fibronectin [FN]), mesenchymal-epithelial transition (MET) (E-cadherin, N-cadherin), and angiogenesis (VEGF, microvessel density [MVD]) were studied by hematoxylin-eosin (HE), Masson staining, and immunohistochemistry. Results demonstrated that TC-Exo treatment effectively promotes regeneration repair of endometrium by relieving fibrosis, enhancing MET, and angiogenesis. These results confirmed new evidence for therapeutic perspective of TC-derived Exo in IUAs.

Characteristics and transcriptomic analysis of scar tissues on the inner uterine cavity wall in patients with intrauterine adhesions

Introduction: It has been previously reported that intrauterine adhesions (IUAs) are the main cause of uterine infertility. However, the histological origin of scar tissue present on the inner wall of the uterine cavity with IUAs has not been previously studied, which is particularly necessary for follow-up research and prevention and treatment. Methods: In this study, myometrium with normal uterus were assigned to the control group and scar tissues with IUAs were assigned to the experimental group. And pathological characteristics and transcriptomic were analyzed between the two groups. Results: We founded no difference was noted in the histological morphology and the α-SMA expression between the experimental and control groups. A total of 698 differentially expressed genes were identified between the two groups. Gene Ontology (GO) analyses revealed that the DEGs were significantly enriched in cell proliferation, AP-1 complex formation, and angiogenesis. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses revealed that the target genes were significantly enriched in the AGE-RAGE, FOXO and TNF signaling pathway. Discussion: As far as we know, this is the first study to propose that the scar tissues are mainly derived from the myometrium and the first one to report differentially expressed genes in the scar tissues of IUAs.

Research progress in the correlation between reproductive tract microbiota and intrauterine adhesion

Intrauterine adhesion (IUA) is caused by damage of the basal layer of endometrium, which leads to fibrosis of the endometrium and the formation of adhesion, resulting in partial or complete occlusion of the uterine cavity, abnormal menstruation, infertility or recurrent miscarriage. The prevalence of IUA in women has been increasing in recent years, and the high recurrence rate of moderate to severe IUA makes IUA treatment more challenging. Iatrogenic endometrial injury is the main cause of IUA. However, the incidence of IUA and the severity of IUA vary among patients who have received similar uterine operations, suggesting that there may be other synergistic factors in the development of IUA. There is a certain correlation between the pathogenesis and the microbiota of the gential tract. In many IUA patients, it has been observed that the probiotics such as Lactobacillus in the vagina is significant reduced, and the pathogenic bacteria such as Gardnerella and Prevotella are excessive growth. The reproductive tract microbiota can be involved in the development and progression of IUA via impacting immune function and metabolism.

Down-Regulating Scar Formation by Microneedles Directly via a Mechanical Communication Pathway

Excessive extracellular matrix deposition drives fibroblasts into a state of high mechanical stress, exacerbating pathological fibrosis and hypertrophic scar formation, leading to tissue dysfunction. This study reports a minimally invasive and convenient approach to obtaining scarless tissue using a silk fibroin microneedle patch (SF MNs). We found that by tuning the MN size and density only, the biocompatible MNs significantly decreased the scar elevation index in the rabbit ear hypertrophic scar model and increased ultimate tensile strength close to regular skin. To advance our understanding of this recent approach, we built a fibroblast-populated collagen lattice system and finite element model to study MN-mediated cellular behavior of fibroblasts. We found that the MNs reduced the fibroblasts generated contraction and mechanical stress, as indicated by decreased expression of the mechanical sensitive gene ANKRD1. Specifically, SF MNs attenuated the integrin-FAK signaling and consequently down-regulated the expression of TGF-β1, α-SMA, collagen I, and fibronectin. It resulted in a low-stress microenvironment that helps to reduce scar formation significantly. Microneedles' physical intervention via the mechanotherapeutic strategy is promising for scar-free wound healing.

miR-29b ameliorates atrial fibrosis in rats with atrial fibrillation by targeting TGFβRΙ and inhibiting the activation of Smad-2/3 pathway

OBJECTIVE

Atrial fibrillation (AF) is a major cause of stroke with lifetime risks. microRNAs (miRNAs) are associated with AF attenuation, yet the mechanism remains unknown. This study investigated the functional mechanism of miR-29b in atrial fibrosis in AF.

METHODS

The AF rat model was established by a 7-day intravenous injection of Ach-CaCl₂ mixture. AF rats were injected with adeno-associated virus (AAv)-miR-29b and TGFβRΙ overexpression plasmid. AF duration was recorded by electrocardiogram. Atrial fibrosis was observed by Masson staining. Expressions of COL1A1, COL3A1, TGFβRΙ, TGFβΙ, miR-29b and Smad-2/3 pathway-related proteins in atrial tissues were detected by RT-qPCR and Western blot. Binding sites of miR-29b and TGFβRΙ were predicted and their target relationship was verified by dual-luciferase reporter assay.

RESULTS

miR-29b was poorly expressed and expressions of COL1A1, COL3A1, TGFβRΙ, and TGFβ1 were increased in atrial tissues of AF rats. miR-29b overexpression alleviated atrial fibrosis, reduced expressions of COL1A1, COL3A1, and TGFβ1, and shortened AF duration in AF rats. TGFβRΙ was highly expressed in atrial tissues of AF rats. miR-29b targeted TGFβRΙ. TGFβRΙ overexpression overcame the improving effect of miR-29b overexpression on AF. miR-29b overexpression decreased ratios of p-Smad-2/3 and Smad-2/3 and inhibited the Smad-2/3 pathway.

CONCLUSION

miR-29b might mitigate atrial fibrosis in AF rats by targeting TGFβRΙ and inhibiting the Smad-2/3 pathway.

Ginkgo biloba leaf extract mitigates cisplatin-induced chronic renal interstitial fibrosis by inhibiting the epithelial-mesenchymal transition of renal tubular epithelial cells mediated by the Smad3/TGF-β1 and Smad3/p38 MAPK pathways

Background

Our previous study indicated that Ginkgo biloba leaf extract (EGb) could protect against cisplatin-induced acute kidney injury in rabbits. The present study aimed to determine the effects and potential molecular mechanisms of EGb on chronic renal interstitial fibrosis induced by cisplatin using in vivo and in vitro models.

Methods

Rats received a single dose of cisplatin on Day 1, and a subset of rats was intraperitoneally injected with EGb daily between Days 22–40. In vitro, HK-2 cells were treated with cisplatin, and a subset of cells was cultivated with EGb or SIS3 (Smad3 inhibitor) for 48 h. Renal function of rats was assessed by detecting the levels of serum creatinine (Scr), blood urea nitrogen (BUN) and urinary N-acetyl-β-D-glucosaminidase (NAG). Hematoxylin and eosin staining and Masson’s trichrome staining were used to evaluate the damage and fibrosis of renal tissue. Western blotting, immunohistochemistry and immunofluorescence were used to detect the protein levels of fibrosis-associated proteins and signaling pathway-related proteins. RT–qPCR analysis was used to examine the mRNA levels of related indicators.

Results

EGb significantly decreased the increased levels of Scr, BUN and urinary NAG and attenuated renal damage and the relative area of renal interstitial fibrosis induced by cisplatin. Additionally, EGb decreased the protein levels of α-SMA, Col I, TGF-β1, smad2/3, phosphorylated (p)-smad2/3, p38 MAPK, and p-p38 MAPK; the ratio of p-p38 MAPK/p38 MAPK; and the mRNA level of p38 MAPK in renal tissues induced by cisplatin. In agreement with in vivo studies, EGb significantly reduced the increased protein levels of these indicators. Additionally, EGb significantly reduced the increased protein levels of vimentin, TIMP-1, and CTGF, as well as the mRNA levels of α-SMA, vimentin, and TGF-β1, while it significantly increased the reduced E-cadherin protein level and the MMP-1/TIMP-1 ratio in HK-2 cells induced by cisplatin. It’s worth noting that the effects of SIS3 in changing the above indicators were similar to those of EGb.

Conclusion

Our study demonstrated that EGb improved cisplatin-induced chronic renal interstitial fibrosis, and its mechanisms were associated with inhibiting the epithelial-mesenchymal transition of renal tubular epithelial cells via the Smad3/TGF-β1 and Smad3/p38 MAPK pathways.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13020-022-00574-y.

Peptidome analysis of human intrauterine adhesion tissues and the identification of antifibrotic peptide

Intrauterine adhesion (IUA) is a common clinical endometrial disease, which can severely damage the fertility and quality of life in women. This study aims to find the differentially expressed endogenous peptides and their possible roles in IUA. Liquid chromatography-mass spectrometry was used to identify the peptidomic profiling of IUA tissues, and the differentially expressed peptides were screened out. Using real-time quantitative PCR, Western blotting, and immunocytochemistry staining, the function of six endogenous peptides was verified in vitro. It was found that peptide 6 (T6) (peptide sequence: TFGGAPGFPLGSPLSSVFPR) could inhibit the expression of TGF-β1-induced cell fibrosis in human endometrial stromal cell line and primary human endometrial stromal cell at a concentration of 50 μmol/L. This study provides new targets for further clarifying the formation and prevention of IUA.

LncRNA TUG1 Regulates Proliferation of Cardiac Fibroblast via the miR-29b-3p/TGF-β1 Axis

Background: Atrial fibrillation (AF) is a very common clinical arrhythmia, accompanied by the overproliferation of cardiac fibroblasts (CFs). This study aimed to investigate the role of the long non-coding RNA(lncRNA) taurine upregulated gene 1 (TUG1) in the proliferation of CFs and further investigated its underlying mechanism.

Methods: One hundred four paroxysmal AF patients and 94 healthy controls were recruited. Human cardiac fibroblasts (HCFs) were applied to establish an AF cell model through treatment with angiotensin II (AngII). qRT-PCR was used for the measurement of gene levels. The cell proliferation was detected by cell counting kit-8 (CCK-8). Luciferase reporter assay was performed for target gene analysis.

Results: Elevated levels of TUG1 and low expression of miR-29b-3p were detected in the serum of AF patients compared with the healthy controls. Pearson's correlation analysis exhibited an inverse relationship between TUG1 and miR-29b-3p expression in AF patients (r = −7.106, p < 0.001). Knockdown of TUG1 inhibited AngII-induced CF proliferation. Taurine upregulated gene 1 (TUG1) functions as a competing endogenous RNA (ceRNA) for miR-29b-3p, and downregulation of miR-29b-3p reversed the role of TUG1 in CF proliferation. TGF-β1 is a direct target gene of miR-29b-3p.

Conclusions: Long non-coding RNA taurine upregulated gene 1 is a key regulator in the occurrence of AF. Slicing TUG1 inhibits CF proliferation by regulating the miR-29b-3p/TGF-β1 axis.

miR‑29a‑3p regulates the epithelial‑mesenchymal transition via the SPARC/ERK signaling pathway in human bronchial epithelial cells

Neutrophilic asthma (NA) is a subtype of asthma that responds poorly to corticosteroid treatment. In certain diseases, microRNA (miR)‑29a‑3p is considered to be a key regulatory molecule for remodeling of the extracellular matrix. However, the effect of miR‑29a‑3p on airway remodeling is unknown. The present study aimed to investigate the role of miR‑29a‑3p in NA. A mouse model of NA was established and these animals were compared to normal controls. Both groups of mice were subjected to lung function tests and histopathological analysis. Human bronchial epithelial cells (16HBE) were grown in culture and incubated with secreted protein acidic rich in cysteine (SPARC) and a miR‑29a‑3p mimic. The expression of miR‑29a‑3p, SPARC and epithelial‑mesenchymal transition (EMT)‑related markers were measured using reverse transcription‑quantitative PCR and western blotting. Luciferase reporter assay was performed to identify the direct regulatory relationship between miR‑29a‑3p and SPARC. miR‑29a‑3p expression was significantly decreased, while SPARC expression was increased in the NA mouse model with a phenotype of EMT. Overexpression of SPARC downregulated the expression of E‑cadherin, while it increased the expression of vimentin in 16HBE cells. miR‑29a‑3p administration reversed the SPARC‑induced effects on E‑cadherin and vimentin expression. Luciferase assays confirmed that SPARC was the target gene for miR‑29a‑3p. Furthermore, SPARC overexpression increased the protein expression of phosphorylated (p)‑ERK, while transfection with miR‑29a‑3p mimics significantly inhibited this increase. The data suggested that EMT in the NA mouse model was associated with decreased levels of miR‑29a‑3p and elevated SPARC. Furthermore, SPARC could induce the formation of EMT in 16HBE cells in vitro and this was directly targeted by miR‑29a‑3p and mediated by p‑ERK, suggesting that miR‑29a‑3p may participate in the airway remodeling of NA.

Repression of Smad4 by MicroRNA-1285 moderates TGF-β-induced epithelial-mesenchymal transition in proliferative vitreoretinopathy

The purpose of this study was to assess whether microRNA (miR)-1285 can suppress the epithelial-mesenchymal transition (EMT) in retinal pigment epithelial cells. Expression of miR-1285 was evaluated using quantitative real-time polymerase chain reaction (RT-qPCR). The features of EMT were assessed using Western blotting, immunocytochemical staining, scratch wound healing tests, modified Boyden chamber assay, and collagen gel contraction assay. A rabbit model of proliferative vitreoretinopathy (PVR) was used for in vivo testing, which involved the induction of PVR by injection of transfected ARPE cells into the vitreous chamber. Luciferase reporter assay was performed to identify the putative target of miR-1285. The expression of miR-1285 was downregulated in ARPE-19 cells treated with transforming growth factor (TGF)-β. Overexpression of miR-1285 led to upregulation of zonula occludens-1, downregulation of α-smooth muscle actin and vimentin, cell migration and cell contractility-all EMT features-in the TGF-β2-treated ARPE-19 cells. The reporter assay indicated that the 3' untranslated region of Smad4 was the direct target of miR1285. PVR progression was alleviated in the miR-1285 transfected rabbits. In conclusion, overexpression of miR-1285 attenuates TGF-β2-induced EMT in a rabbit model of PVR, and the effect of miR-1285 in PVR is dependent on Smad4. Further research is warranted to develop a feasible therapeutic approach for the prevention and treatment of PVR.

Downregulation of miR-29b is associated with Peyronie's disease

BACKGROUND

Peyronie's disease (PD) is characterized by the formation of fibrous plaque in tunica albuginea, causing several problems in patients. The etiology of this disease is not fully understood, and there are few effective treatments. To better understand the molecular pathways of PD, we studied miR-29b, a microRNA that could be involved with this illness. MicroRNAs are endogenous molecules that act by inhibiting messenger RNA. MiR-29b regulates 11 of 20 collagen genes and the TGF-β1 gene, which are related to PD progression.

METHODS

We compared miR-29b expression in 11 patients with PD and 14 patients without PD (control group). For the patients with PD, we utilized samples from the fibrous plaque (n = 9), from the tunica albuginea (n = 11), and from the corpus cavernosum (n = 8). For the control group, we utilized samples from the tunica albuginea (n = 14) and from the corpus cavernosum (n = 10). MiR-29b expression was determined by q-PCR.

RESULTS

We found a downregulation of miR-29b in the fibrous plaque, tunica albuginea and corpus cavernosum of patients with PD in comparison with the control group (p = 0.0484, p = 0.0025, and p = 0.0016, respectively).

CONCLUSION

Although our study has a small sample, we showed for the first time an evidence that the downregulation of miR-29b is associated with PD.

TGF-β signaling and microRNA cross-talk regulates abdominal aortic aneurysm progression

Abdominal aortic aneurysms (AAA) are permanent and irreversible local dilatations of the abdominal aortic wall. Recent data indicate that the transforming growth factor-beta (TGF-β) signaling pathway exerts a protective effect on the development of AAA. Some dysregulated microRNAs (miRNA) also appear involved in the expansion of AAA and miRNA-based therapeutics have been shown to effectively inhibit this process. New evidence has revealed that TGF-β signaling and miRNA interaction may of physiologic and pathophysiologic significance including the progression of AAA. As such, miRNA that regulate TGF-β signaling may hold promise as potential therapeutic targets. This review explores potential crosstalk between TGF-β signaling and miRNA in AAA in order improve our understanding of this pathology and explore development of potential therapeutic targets.

LncRNA HOTAIR promotes endometrial fibrosis by activating TGF-β1/Smad pathway

Homeobox transcript antisense RNA (HOTAIR) is a long non-coding RNA associated with a number of fibrosis-related diseases. The aim of this study was to investigate the specific role of HOTAIR in the development of endometrial fibrosis and to identify the molecular mechanisms underlying this process. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to determine the expression levels of HOTAIR in samples of intrauterine adhesion (IUA) tissue and in endometrial stromal cells (ESCs) that had been treated with transforming growth factor beta 1 (TGF-β1). Additionally, we transfected ESCs with either overexpression plasmid (pcDNA-HOTAIR) or silencing construct (si-HOTAIR) and then treated these cells with TGF-β1. We then performed RT-qPCR and western blot analysis, along with cell proliferation and apoptosis assays, to investigate the effects of HOTAIR on the transdifferentiation of ESCs into myofibroblasts. The results showed that the expression levels of HOTAIR were significantly elevated in IUA tissue and in ESCs that had been treated with TGF-β1. The overexpression of HOTAIR had a pro-fibrotic effect on ESCs, while the silencing of HOTAIR exerted an anti-fibrotic effect. Most importantly, the protein expression levels of p-Smad2 and p-Smad3 were significantly upregulated in TGF-β1-treated ESCs transfected with pcDNA-HOTAIR and were downregulated after transfection with si-HOTAIR constructs. These data indicate that HOTAIR promotes endometrial fibrosis by activating the TGF-β1/Smad signaling pathway, suggesting that the inhibition of HOTAIR may represent a promising therapeutic option for suppressing endometrial fibrosis.

si-SNHG5-FOXF2 inhibits TGF-β1-induced fibrosis in human primary endometrial stromal cells by the Wnt/β-catenin signalling pathway

Background

Intrauterine adhesions (IUAs) are manifestations of endometrial fibrosis characterized by inflammation and fibrinogen aggregation in the extracellular matrix (ECM). The available therapeutic interventions for IUA are insufficiently effective in the clinical setting for postoperative adhesion recurrence and infertility problems. In this study, we investigated whether si-SNHG5-FOXF2 can serve as a molecular mechanism for the inhibition of IUA fibrosis ex vivo.

Methods

FOXF2, TGF-β1 and collagen expression levels were measured by microarray sequencing analysis in three normal endometrium groups and six IUA patients. We induced primary human endometrial stromal cells (HESCs) into myofibroblasts (MFs) to develop an IUA cell model with various concentrations of TGF-β1 at various times. Downstream target genes of FOXF2 were screened by chromatin immunoprecipitation combined with whole-genome high-throughput sequencing (ChIP-seq). We investigated ECM formation, cell proliferation and Wnt/β-catenin signalling pathway-related proteins in primary HESCs with FOXF2 downregulation by quantitative reverse transcription-polymerase chain reaction (qRT-PCR), western blotting (WB), immunohistochemistry (IHC), flow cytometry, ethylenediurea (EdU) and CCK8 assays. We identified long noncoding RNAs (lncRNA) SNHG5 as the upstream regulatory gene of FOXF2 through RNA immunoprecipitation (RIP), RNA pulldown and fluorescence in situ hybridization (FISH). Finally, we examined FOXF2 expression, ECM formation, cell proliferation and Wnt/β-catenin signalling pathway-related proteins in primary HESCs upon FOXF2 downregulation.

Results

FOXF2 was highly expressed in the endometrium of patients with IUA. Treatment of primary HESCs with 10 ng/ml TGF-β1 for 72 h was found to be most effective for developing an IUA cell model. FOXF2 regulated multiple downstream target genes, including collagen, vimentin (VIM) and cyclin D2/DK4, by ChIP-seq and ChIP-PCR. FOXF2 downregulation inhibited TGF-β1-mediated primary HESC fibrosis, including ECM formation, cell proliferation and Wnt/β-catenin signalling pathway-related protein expression. We identified lncRNA SNHG5 as an upstream gene that directly regulates FOXF2 by RIP-seq, qRT-PCR, WB and FISH. SNHG5 downregulation suppressed FOXF2 expression in the IUA cell model, resulting in synergistic repression of the Wnt/β-catenin pathway, thereby altering TGF-β1-mediated ECM aggregation in endometrial stromal cells ex vivo.

Conclusions

Regulation of the Wnt/β-catenin signalling pathway and ECM formation by si-SNHG5-FOXF2 effectively inhibited the profibrotic effect of TGF-β1 on primary HESCs. This finding can provide a molecular basis for antagonizing TGF-β1-mediated fibrosis in primary HESCs.

Recent Advances in Understandings Towards Pathogenesis and Treatment for Intrauterine Adhesion and Disruptive Insights from Single-Cell Analysis

Intrauterine adhesion is a major cause of menstrual irregularities, infertility, and recurrent pregnancy losses and the progress towards its amelioration and therapy is slow and unsatisfactory. We aim to summarize and evaluate the current treatment progress and research methods for intrauterine adhesion. We conducted literature review in January 2020 by searching articles at PubMed on prevention and treatment, pathogenesis, the repair of other tissues/organs, cell plasticity, and the stem cell–related therapies for intrauterine adhesion. A total of 110 articles were selected for review. Uterine cell heterogeneity, expression profile, and cell-cell interaction were investigated based on scRNA-seq of uterus provided by Human Cell Landscape (HCL) project. Previous knowledge on intrauterine adhesion (IUA) pathogenesis was mostly derived from correlation studies by differentially expressed genes between endometrial tissue of intrauterine adhesion patients/animal models and normal endometrial tissue. Although the TGF-β1/SMAD pathway was suggested as the key driver for IUA pathogenesis, uterine cell heterogeneity and distinct expression profile among different cell types highlighted the importance of single-cell investigations. Cell-cell interaction in the uterus revealed the central hub of endothelial cells interacting with other cells, with endothelial cells in endothelial to mesenchymal transition and fibroblasts as the strongest interaction partners. The potential of stem cell–related therapies appeared promising, yet suffers from largely animal studies and nonstandard study design. The need to dissect the roles of endometrial cells, endothelial cells, and fibroblasts and their interaction is evident in order to elucidate the molecular and cellular mechanisms in both intrauterine adhesion pathogenesis and treatment.

Quercetin regulates fibrogenic responses of endometrial stromal cell by upregulating miR-145 and inhibiting the TGF-β1/Smad2/Smad3 pathway

OBJECTIVES

Aim of this study is to explore whether quercetin can inhibit the enlarged fibrogenic responses of endometrial stromal cells by increasing the level of microRNA-145 (miR-145) and mediating the TGFβ1/Smad2/Smad3 signaling pathway, and to discuss the mechanism of signal transduction, further to provide experimental basis for revealing the pathophysiological mechanism and seeking new strategies for effective prevention and treatment of endometrial fibrosis.

METHODS

The expression levels of miR-145 and TGF-β receptor 2 (TGFBR2) were detected by RT-qPCR analysis. Expressions of α-smooth muscle actin (α-SMA) and vimentin were examined by immunofluorescence staining. Cell viability was measured by MTT assay. The protein expression of collagen type 1 alpha 1 (Col1a1), α-SMA, fibronectin (FN), TGFBR2, transforming growth factor (TGF-β1), Smad2/3, phospho-Smad2/3 (p-Smad2/3) were detected by western blot analysis. The interaction between miR-145 and TGFBR2 was confirmed by dual-luciferase reporter gene assay.

RESULTS

The expression level of miR-145 was decreased, whereas TGFBR2 was increased in intrauterine adhesion tissue. The expression levels of COL1A1, α-SMA, FN, TGFBR2, and p-Smad2/3 were increased, whereas miR-145 and cell proliferation were decreased in human endometrial stromal cells (hESCs) in response to TGF-β1 stimulation in a time and dose-dependent manner, which could be reversed by quercetin. Furthermore, quercetin regulates cell fibrogenic responses of endometrial stromal cells via miR-145/TGF-β1/Smad2/Smad3 pathway.

CONCLUSIONS

These findings indicated that quercetin have a significant anti-fibrotic effect and could upregulate miR-145 and inhibit activation of TGF-β1/Smad2/Smad3 pathway to regulate TGF-β1 induced fibrogenic responses of endometrial stromal cells, which may serve as a potential therapeutic agent for endometrial fibrosis.

miR-363 Alleviates Detrusor Fibrosis via the TGF-β1/Smad Signaling Pathway by Targeting Col1a2 in Rat Models of STZ-Induced T2DM

Dysregulated expression of microRNAs (miRNAs or miRs) has been implicated in the pathophysiology of type 2 diabetes mellitus (T2DM). However, their underlying role in the complication of detrusor fibrosis remains poorly understood. Therefore, this study aimed to examine the potential functional relevance of miR-363 in detrusor fibrosis of rats with streptozotocin (STZ)-induced T2DM through the predicted target gene collagen type I alpha 2 (Col1a2). Immunohistochemical analysis found an increase in the positive expression of collagen type III alpha 1 (Col3a1) and Col1a2 in detrusor tissues, where miR-363 expression was decreased. Next, gain- and loss-of-function experiments were performed to clarify the effects of miR-363 and Col1a2 on the activities of bladder detrusor cells. Of note, binding affinity between miR-363 and Col1a2 was verified by a dual-luciferase reporter gene assay and RNA immunoprecipitation (RIP) assay. Upregulated miR-363 inhibited Col1a2 expression, which led to increased expression of B-cell lymphoma 2 (Bcl-2) and Smad7 and accelerated cell viability, along with decreases in cell apoptosis and Col3a1, Bcl-2-associated X protein (Bax), transforming growth factor (TGF)-β1, and Smad4 expressions. In conclusion, miR-363 upregulation reduces detrusor fibrosis in rats with STZ-induced T2DM through suppression of the TGF-β1/Smad signaling pathway by targeting Col1a2. Therefore, our study provided further insights for the development of new therapeutic targets for T2DM.

Transforming growth factor-β1 in intrauterine adhesion

Intrauterine adhesion (IUA), led by trauma to the basal layer, can prevent the endometrium from growing, resulting in complications in females, such as infertility and amenorrhea. Transforming growth factor-β1 (TGF-β1) plays a crucial role in inducing and promoting the differentiation and proliferation of mesenchymal cells, in the secretion of extracellular matrix-associated components, and is a major cytokine in initiating and terminating tissue repair downstream of the TGF-β/Smad signaling pathway. Some evidence supports that TGF-β1 is closely associated with the occurrence and development of IUA, and is regarded as an early risk factor of disease recurrence. Furthermore, the role of TGF-β1 has been demonstrated to be potentially regulated by a variety of cytokines, hormones, enzymes, and microRNAs. This review provides an overview of the expression, function, and regulation of TGF-β1 in IUA, with a brief discussion and perspectives on its future clinical implications on the diagnosis and treatment of IUA.

Functional analysis of miRNAs combined with TGF-β1/Smad3 inhibitor in an intrauterine rat adhesion cell model

In this study, we aimed to study the role of miRNAs in intrauterine adhesion (IUA) disease. An IUA cell model was constructed by TGF-β1. Smad3 inhibitor (SIS3) can inhibit the Smad3 signaling pathway and affect the role of TGF-β1; thus, it was used to identify the role of Smad3 and related miRNAs in IUA. Cell number significantly increased in the TGF-β1 group after 72 h and 96 h, respectively, compared with that in the control group (P < 0.05). However, cell proliferation was significantly decreased in the TGF-β1 + SIS3 group (P < 0.0001). Cell apoptosis was increased in the TGF-β1 + SIS3 group compared with that in the TGF-β1 group. Western Blot (WB) analysis suggested that TGF-β1 treatment could effectively increase the expression of α-SMA, COL1, Smad3, and p-Smad3, which could be inhibited by SIS3 treatment. A total of 235 and 530 differentially expressed miRNAs in the TGF-β1 + SIS3 group were significantly up- and downregulated compared with those in the TGF-β1 group, respectively. These differentially expressed miRNAs were enriched in the MAPK and PI3K-AKT pathways. The ten most differentially expressed miRNAs were selected to verify their expressions using quantitative real-time polymerase chain reaction (qPCR). Furthermore, overexpression of rno-miR-3586-3p and rno-miR-455-5p can promote cell proliferation and exacerbate the IUA pathogenic process. However, overexpression of rno-miR-204-3p and rno-miR-3578 can inhibit cell behavior and IUA progression. The above results can provide detailed information for the understanding of IUA molecular mechanisms.

Aspirin inhibits endometrial fibrosis by suppressing the TGF‑β1‑Smad2/Smad3 pathway in intrauterine adhesions

Intrauterine adhesions (IUAs) represent one of the most common diseases in women of reproductive age. Patients with moderate‑to‑severe IUA can experience a decrease in normal menstrual patterns, amenorrhea and even infertility. At present, the first‑line treatment strategies for IUAs in the clinical practice are hysteroscopic transuterine resection of adhesion and postoperative adjuvant therapy, including oestrogen. However, a high recurrence rate of IUAs remains. In recent years, studies have demonstrated that aspirin combined with oestrogen may significantly prevent the postoperative disease recurrence rate, improve endometrial receptivity and improve the conception rate by increasing endometrial blood supply and angiogenesis more effectively. The TGF‑β1‑Smad2/Smad3 pathway is one of the important mechanisms involved in endometrial fibrosis. However, whether aspirin can inhibit endometrial fibrosis through the TGF‑β1‑Smad2/Smad3 pathway to prevent postoperative re‑adhesion remains to be elucidated. The results of the present study suggested that aspirin inhibits endometrial fibrosis by suppressing the TGF‑β1‑Smad2/Smad3 pathway, which may provide new hypotheses for the mechanism of action of aspirin in the treatment of IUAs.

Foxf2 and Smad6 co-regulation of collagen 5A2 transcription is involved in the pathogenesis of intrauterine adhesion

The replacement of normal endometrial epithelium by fibrotic tissue is the pathological feature of intrauterine adhesion (IUA), which is caused by trauma to the basal layer of the endometrium. COL5A2 is a molecular subtype of collagen V that regulates collagen production in fibrotic tissue. Here, we investigated the roles of Foxf2 and Smad6 in regulating the transcription of COL5A2 and their involvement in the pathogenesis of IUA. Small interference‐mediated Foxf2 (si‐Foxf2) silencing and pcDNA3.1‐mediated Smad6 (pcDNA3.1‐Smad6) up‐regulation were performed in a TGF‐β1‐induced human endometrial stromal cell line (HESC) fibrosis model. Assessment of collagen expression by Western blotting, immunofluorescence and qRT‐PCR showed that COL5A2, COL1A1 and FN were significantly down‐regulated in response to si‐Foxf2 and pcDNA3.1‐Smad6. Transfection of lentivirus vector‐Foxf2 (LV‐Foxf2) and pcDNA3.1‐Smad6 into HESCs and qRT‐PCR showed that Foxf2 promoted COL5A2 expression and Smad6 inhibited Foxf2‐induced COL5A2 expression. Co‐immunoprecipitation, chromatin immunoprecipitation and dual‐luciferase reporter assays to detect the interaction between Foxf2 and Smad6 and their role in COL5A2 transcription showed that Foxf2 interacted with Smad6 and bond the same promoter region of COL5A2. In a rat IUA model, injection of ADV2‐Foxf2‐1810 and ADV4‐Smad6 into the uterine wall showed that Foxf2 down‐regulation and Smad6 up‐regulation decreased fibrosis and the expression of COL5A2 and COL1A1, as detected by haematoxylin/eosin, Masson trichrome staining and immunohistochemistry. Taken together, these results suggested that Foxf2 interacted with Smad6 and co‐regulated COL5A2 transcription in the pathogenesis of IUA, whereas they played opposite roles in fibrosis.

tRNA‑derived small RNAs: A novel class of small RNAs in human hypertrophic scar fibroblasts

tRNA-derived small RNAs (tsRNAs) have been shown to play regulatory roles in many physiological and pathological processes. However, their roles in hypertrophic scars remain unclear. The present study investigated differentially expressed tsRNAs in human hypertrophic scar fibroblasts and normal skin fibroblasts via high-throughput sequencing. Several dysregulated tsRNAs were validated by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment, target prediction, coexpression networks and competing endogenous RNA (ceRNA) networks were evaluated to discover the principal functions of significantly differentially expressed tsRNAs. In total, 67 differentially expressed tsRNAs were detected, of which 27 were upregulated and 40 downregulated in hyper-trophic scar fibroblasts. The GO analysis indicated that the dysregulated tsRNAs are associated with numerous biological functions, including 'nervous system development', 'cell adhesion', 'focal adhesion', 'protein binding', 'angiogenesis' and 'actin binding'. KEGG pathway analysis revealed that the most altered pathways include 'Ras signaling pathway', 'Rap1 signaling pathway' and 'cGMP-PKG signaling pathway'. The target genes of the differentially expressed tsRNAs participate in several signaling pathways important for scar formation. The results of RT-qPCR were consistent with those of sequencing. MicroRNA (miR)-29b-1-5p was identified as a target of tsRNA-23678 and was downregulated in hypertrophic scar fibroblasts, constituting a negative regulatory factor for scar formation. Furthermore, tsRNA-23761 acted as a ceRNA and bound to miR-3135b to regulate the expression of miR-3135b targets, including angiotensin-converting enzyme. Collectively, these findings reveal that tsRNAs are differentially expressed in human hypertrophic scar fibroblasts, and may contribute to the molecular mechanism and treatment of hypertrophic scars.

The polysaccharides from Grifola frondosa attenuate CCl4-induced hepatic fibrosis in rats via the TGF-β/Smad signaling pathway

The TGF-β1/Smad signaling pathway has been linked to hepatic fibrosis. Previous studies have shown that yellow polysaccharide can prevent the development of hepatic fibrosis. However, it is unclear whether the polysaccharide affects the TGF-β1/Smad signaling pathway. In this experiment, 50 experimental rats were randomly divided into a normal control group, model group, low GFP dose group (50 mg kg^-1), medium GFP dose group (100 mg kg^-1), and high GFP dose group (200 mg kg^-1). A cirrhotic portal hypertension rat model was established by a CCl₄ compound method. After 12 weeks of intragastric administration, the liver index of the medium dose and high dose group was significantly lower than that of the model group. The hepatic fibrosis lesions of rats in each dose group were improved to different extents, and the effect was most significant in the high dose group. The contents of ALT, AST, TBIL and CIV, PCIII, LN and HA in serum were significantly decreased. The activity of SOD and GSH-Px in the liver tissue of GFP medium and high dose groups was significantly increased and the content of MDA was significantly decreased. The contents of TNF-α, IL-1β and IL-6 were significantly decreased. The western blot results showed that the expressions of p-Smad 2/3, Smad4, PAI-1, Imp7 and Imp8 in medium dose and high dose groups were significantly lower than those in the model group, while the expression of Smad7 was significantly higher than that of the model group. The GFP-treated group was able to reduce the expression level of mi R-154 in liver tissue and increase the expression level of miR-146a. GFP has a significant intervention effect on rat hepatic fibrosis, and its mechanism may inhibit the progression of hepatic fibrosis by inhibiting oxidative stress and inflammatory response and regulating TGF-β1/Smad signaling pathway and mi RNA expression.

The lncRNA NEAT1/miR-29b/Atg9a axis regulates IGFBPrP1-induced autophagy and activation of mouse hepatic stellate cells

AIMS

Insulin-like growth factor binding protein-related protein 1 (IGFBPrP1) promotes hepatic stellate cell (HSC) autophagy and activation. However, the underlying mechanism remains unknown. Noncoding RNAs (ncRNAs) including long noncoding RNAs (lncRNAs) and microRNAs (miRNAs), have received increasing attention. We aimed to investigate the roles of the lncRNA nuclear enriched abundant transcript 1 (NEAT1), miR-29b, and autophagy related protein 9a (Atg9a), and their relationships with each other during IGFBPrP1-induced HSC autophagy and activation.

MAIN METHODS

Levels of NEAT1, miR-29b, Atg9a, and autophagy were detected in adenovirus-mediated IGFBPrP1 (AdIGFBPrP1)-treated mouse liver tissue and immortalized mouse hepatic stellate cell line JS1 transfected with either AdIGFBPrP1 or siIGFBPrP1. In AdIGFBPrP1-treated JS1 cells, autophagy and activation were detected after altering NEAT1, miR-29b, or Atg9a levels. In AdIGFBPrP1-treated JS1 cells, relationships among NEAT1, miR-29b, and Atg9a were explored using dual-luciferase reporter assays, Western blot, qRT-PCR, and immunofluorescence.

KEY FINDINGS

IGFBPrP1 increased levels of NEAT1, Atg9a, and autophagy while decreasing the level of miR-29b in mouse liver tissues and mouse HSCs. Moreover, NEAT1 increased HSC autophagy and activation while miR-29b decreased both processes. Atg9a also participated in IGFBPrP1-induced HSC autophagy and activation. Importantly, NEAT1, miR-29b, and Atg9a formed a NEAT1/miR-29b/Atg9a regulatory axis for IGFBPrP1-induced HSC autophagy and activation.

SIGNIFICANCE

Our study unveiled the new NEAT1/miR-29b/Atg9a regulatory axis involved in IGFBPrP1-induced mouse HSC autophagy and activation. The study thus provides new insights in the pathogenesis and potential therapeutic strategies of liver fibrosis.

Smad signaling coincides with epithelial-mesenchymal transition in a rat model of intrauterine adhesion

PURPOSE

Intrauterine adhesion (IUA) is a fibrotic disease mainly caused by tissue injury, yet the mechanism is poorly understood. The aim of this study was to investigate the roles of TGF-β1/BMP7/Smad signaling coincident with epithelial-mesenchymal transition (EMT) in IUA.

METHODS

Twenty-four female SD rats were divided into IUA and sham groups. For each animal, a mechanical injury or sham operation was performed on the left uterus (IUA-L, Sham-L), and the right uterus (IUA-R, Sham-R) was used as the control. Animals were sacrificed in batches on days 7 and 28. The endometrial morphology, number of endometrial glands, microvascular density (MVD), area of endometrial fibrosis and immunohistochemistry (IHC) analysis of biomarkers of EMT, as well as levels of TGF-β1, phosphorylated Smad3 (pSmad3), BMP7, phosphorylated Smad1/5 (pSmad1/5) and estrogen receptor (ER) were evaluated. Besides, the correlation between these IHC markers was also analyzed. RT-PCR and western blot were used to test relevant genes.

RESULTS

Compared with other groups, the IUA-L group showed a significant decrease in the number of glands and MVD. And it also showed a significant increase in the stromal fibrosis rate and a-SMA level. Moreover, in the IUA-L group, TGF-β1 and pSmad3 levels were consistently high, and levels of BMP7, pSmad1/5 and ER were low. EMT markers E-cadherin was decreased, while N-cadherin was increased. Sham and control groups showed no significant difference in these markers. In addition, E-cadherin with a-SMA, fibrosis rate with BMP7, TGF-β1 with pSmad3 and BMP7 with pSmad1/5 showed correlation in IUA-L group, which had statistical significance. The mRNA expression of TGF-β1, a-SMA and ccn2 in 7 d IUA-L was higher than 7 d IUA-R while BMP7 was lower, which had significant difference. The protein expression of BMP7 in 7 d IUA-L was lower than 7 d IUA-R, which had significant difference.

CONCLUSIONS

These results suggest a potential role of Smad signaling together with EMT in endometrial fibrosis development.

miR-29c improves skeletal muscle mass and function throughout myocyte proliferation and differentiation and by repressing atrophy-related genes

AIM

To identify microRNAs (miRs) involved in the regulation of skeletal muscle mass. For that purpose, we have initially utilized an in silico analysis, resulting in the identification of miR-29c as a positive regulator of muscle mass.

METHODS

miR-29c was electrotransferred to the tibialis anterior to address its morphometric and functional properties and to determine the level of satellite cell proliferation and differentiation. qPCR was used to investigate the effect of miR-29c overexpression on trophicity-related genes. C2C12 cells were used to determine the impact of miR-29c on myogenesis and a luciferase reporter assay was used to evaluate the ability of miR-29c to bind to the MuRF1 3'UTR.

RESULTS

The overexpression of miR-29c in the tibialis anterior increased muscle mass by 40%, with a corresponding increase in fibre cross-sectional area and force and a 30% increase in length. In addition, satellite cell proliferation and differentiation were increased. In C2C12 cells, miR-29c oligonucleotides caused increased levels of differentiation, as evidenced by an increase in eMHC immunostaining and the myotube fusion index. Accordingly, the mRNA levels of myogenic markers were also increased. Mechanistically, the overexpression of miR-29c inhibited the expression of the muscle atrophic factors MuRF1, Atrogin-1 and HDAC4. For the key atrogene MuRF1, we found that miR-29c can bind to its 3'UTR to mediate repression.

CONCLUSIONS

The results herein suggest that miR-29c can improve skeletal muscle size and function by stimulating satellite cell proliferation and repressing atrophy-related genes. Taken together, our results indicate that miR-29c might be useful as a future therapeutic device in diseases involving decreased skeletal muscle mass.

Establishment and comparison of different intrauterine adhesion modelling procedures in rats

Intrauterine adhesion (IUA) is caused by endometrial damage and leads to the formation of scar fibrosis and repair disorders. We compared four different rat IUA modelling procedures in order to establish a stable animal model suitable for investigating IUA. Twenty female Sprague--Dawley rats were randomly divided into four groups. IUA was induced on one side of each rat uterus by ethanol instillation, heat stripping, mechanical injury or mechanical injury with infection (dual-injury); the other side of the uterus was left intact as a control. After 8 days the rats were sacrificed, their uteri were examined for histomorphology and expression of endometrial markers was checked using immunohistochemistry. All four IUA modelling procedures resulted in visual pathophysiological changes in the rat uterus, including stenosis, congestion and loss of elasticity. Endometrial thinning, shrinkage of glands and formation of fibrotic hyperplasia were also observed. All four procedures resulted in the downregulation of cytokeratin 18 and vimentin expression compared with control tissues, as well as the upregulation of collagen I expression. After mechanical injury and dual-injury the expression of interleukin 6 was significantly increased. Overall, our results suggest that ethanol instillation is the most stable IUA modelling procedure. Mechanical injury reliably yielded inflammatory indicators.

MicroRNA as novel biomarkers and therapeutic targets in diabetic kidney disease: An update

Diabetic kidney disease (DKD) is a life-limiting condition characterized by progressive and irreversible loss of renal function. Currently, the estimated glomerular filtration rate (eGFR) and albuminuria are used as key markers to define DKD. However, they may not accurately indicate the degree of renal dysfunction and injury. Current therapeutic approaches for DKD, including attainment of blood pressure goals, optimal control of blood glucose and lipid levels, and the use of agents to block the renin-angiotensin-aldosterone system (RAAS) can only slow the progression of DKD. Hence, early diagnosis and innovative strategies are needed to both prevent and treat DKD. In recent years, a novel class of noncoding RNA, microRNAs (miRNAs) are reported to be involved in all biological processes, including cellular proliferation, apoptosis, and differentiation. miRNAs are small noncoding RNAs that regulate gene expression by posttranscriptional and epigenetic mechanisms. They are found to be in virtually all body fluids and used successfully as biomarkers for various diseases. Urinary miRNAs correlate with clinical and histologic parameters in DKD and differential urinary miRNA expression patterns have been reported. Kidney fibrosis is the common end stage of various CKD including DKD. Transforming growth factor-β(TGF-β) is regarded as the master regulator of kidney fibrosis, which is likely at least in part through regulating miRNA expression. miRNA are widely involved in the progression of DKD via many molecular mechanisms. In this review, the involvement of miRNA in fibrosis, inflammation, hypertrophy, autophagy, endoplasmic reticulum (ER) stress, oxidative stress, insulin resistance, and podocyte injury will be discussed, as these mechanisms are believed to offer new therapeutic targets that can be exploited to develop important treatments for DKD over the next decade.

MiR-130b increases fibrosis of HMC cells by regulating the TGF-β1 pathway in diabetic nephropathy

Basement membrane thickening, glomerular hypertrophy, and deposition of multiple extracellular matrix characterize the pathological basis of diabetic nephropathy (DN), a condition which ultimately leads to glomerular and renal interstitial fibrosis. Here, we identified a novel microRNA, miR-130b, and investigated its role and therapeutic efficacy in alleviating DN. Introduction of miR-130b dramatically increased cell growth and fibrosis in DN cells. We found that transforming growth factor (TGF)-β1 was a functional target of miR-130b in human glomerular mesangial cells (HMCs) and overexpression of miR-130b increased expressions of the downstream signaling molecules of TGF-β1, t-Smad2/3, p-Smad2/3, and SMAD4. An ectopic application of miR-130b increased messenger RNA and protein expressions of collagen type I (colI), colIV, and fibronectin, whose expression levels were correlated with the expression of miR-130b. Taken together, the findings of this study reveal that miR-130b in HMC cells plays an important role in fibrosis regulation and may thus be involved with the pathogenesis of DN. Therefore, miR-130b may serve as a novel therapeutic target for the prevention and the treatment of DN.

Chronic Niche Inflammation in Endometriosis-Associated Infertility: Current Understanding and Future Therapeutic Strategies

Endometriosis is an estrogen-dependent inflammatory disease that affects up to 10% of women of reproductive age and accounts for up to 50% of female infertility cases. It has been highly associated with poorer outcomes of assisted reproductive technology (ART), including decreased oocyte retrieval, lower implantation, and pregnancy rates. A better understanding of the pathogenesis of endometriosis-associated infertility is crucial for improving infertility treatment outcomes. Current theories regarding how endometriosis reduces fertility include anatomical distortion, ovulatory dysfunction, and niche inflammation-associated peritoneal or implantation defects. This review will survey the latest evidence on the role of inflammatory niche in the peritoneal cavity, ovaries, and uterus of endometriosis patients. Nonhormone treatment strategies that target these inflammation processes are also included. Furthermore, mesenchymal stem cell-based therapies are highlighted for potential endometriosis treatment because of their immunomodulatory effects and tropism toward inflamed lesion foci. Potential applications of stem cell therapy in treatment of endometriosis-associated infertility in particular for safety and efficacy are discussed.

Mir-29b promotes human aortic valve interstitial cell calcification via inhibiting TGF-β3 through activation of wnt3/β-catenin/Smad3 signaling

Herein, we hypothesized that pro-osteogenic MicroRNAs (miRs) could play functional roles in the calcification of the aortic valve and aimed to explore the functional role of miR-29b in the osteoblastic differentiation of human aortic valve interstitial cells (hAVICs) and the underlying molecular mechanism. Osteoblastic differentiation of hAVICs isolated from human calcific aortic valve leaflets obtained intraoperatively was induced with an osteogenic medium. Alizarin red S staining was used to evaluate calcium deposition. The protein levels of osteogenic markers and other proteins were evaluated using western blotting and/or immunofluorescence while qRT-PCR was applied for miR and mRNA determination. Bioinformatics and luciferase reporter assay were used to identify the possible interaction between miR-29b and TGF-β3. Calcium deposition and the number of calcification nodules were pointedly and progressively increased in hAVICs during osteogenic differentiation. The levels of osteogenic and calcification markers were equally increased, thus confirming the mineralization of hAVICs. The expression of miR-29b was significantly increased during osteoblastic differentiation. Furthermore, the osteoblastic differentiation of hAVICs was significantly inhibited by the miR-29b inhibition. TGF-β3 was markedly downregulated while Smad3, Runx2, wnt3, and β-catenin were significantly upregulated during osteogenic induction at both the mRNA and protein levels. These effects were systematically induced by miR-29b overexpression while the inhibition of miR-29b showed the inverse trends. Moreover, TGF-β3 was a direct target of miR-29b. Inhibition of miR-29b hinders valvular calcification through the upregulation of the TGF-β3 via inhibition of wnt/β-catenin and RUNX2/Smad3 signaling pathways.

Human mesenchymal stem cell-derived extracellular vesicles/estrogen combined therapy safely ameliorates experimentally induced intrauterine adhesions in a female rat model

BACKGROUND

Mesenchymal stem cells (MSCs) have diverse functions in regulating injury and inflammation through the secretion of extracellular vesicles (EVs).

METHODS

In this study, we investigated the systemic administration of extracellular vesicles derived from human umbilical cord mesenchymal stem cells (UCMSCs-EVs) as a therapeutic agent for intrauterine adhesions (IUAs) caused by endometrial injury. Additionally, we investigated the therapeutic impact of both UCMSCs-EVs and estrogen either separately or in combination in a rat model. The inflammation, vascularization, proliferation, and extent of fibrosis were assessed by a histopathological and immunohistochemical assessment using transforming growth factor (TGF)-β as a fibrotic marker and vascular endothelial growth factor (VEGF) as a vascular marker. Additionally, quantitative real-time polymerase chain reaction (qRT-PCR) was used to analyze the expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1, IL-6 (inflammatory cytokines), CD140b (a marker of endometrial stem cells), and RUNX2 (an antifibrotic factor). Finally, Western blotting was used to evaluate collagen I and β-actin expression.

RESULTS

The therapeutic groups treated with either UCMSCs-EVs alone or combined with estrogen exhibited a significant decrease in inflammation and fibrosis (TNF-α, TGF-β, IL-1, IL-6, RUNX2, and collagen-I) as well as a significant decrease in vascularization (VEGF) compared with the untreated rats with IUAs. The most significant results were obtained in animals with IUAs that received a combined therapy of UCMSCs-EVs and estrogen.

CONCLUSIONS

We conclude that the synergistic action of human UCMSCs-EVs combined with estrogen provides a highly effective alternative regenerative agent in IUA treatment.

MicroRNA‑326 inhibits endometrial fibrosis by regulating TGF‑β1/Smad3 pathway in intrauterine adhesions

Intrauterine adhesion (IUA), characterized by endometrial fibrosis, may lead to infertility and recurrent pregnancy loss. At present, there is no ideal therapy for IUA. Recent findings have revealed that microRNAs (miRNAs) have a decisive role in the regulation of fibrosis. The aim of the present study was to investigate the molecular mechanism of miRNAs in endometrial fibrosis. The present study compared the expression profiles of miRNAs between endometrial tissues from patients with IUA and normal endometrial tissues using microarray analysis. Validation of miR‑326 level in endometrial tissues was performed using reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR). Subsequently, the effects of miR‑326 on fibrotic markers including α‑smooth muscle actin (α‑SMA), collagen type I α 1 chain (COL1A1), transforming growth factor‑β1 (TGF‑β1) and fibronectin (FN), were evaluated in endometrial tissues and endometrial stromal cells (ESCs) from patients with IUA. Additional bioinformatics analysis, luciferase reporter assays, RT‑qPCR and western blotting were performed to identify target genes. Additionally, the expression levels of TGF‑β1, p‑Smad3 and Smad3 were quantified to determine whether the anti‑fibrotic role of miR‑326 was associated with the activity of the TGF‑β1/Smad3 signaling pathway. The present study determined that miR‑326 was downregulated in endometrial tissues from patients with IUA and miR‑326 levels were inversely correlated with the expression of TGF‑β1, α‑SMA, COL1A1 and FN. Additional findings revealed that overexpression of miR‑326 inhibited endometrial fibrosis by downregulating these pro‑fibrotic genes. TGF‑β1, an important pro‑fibrogenic mediator, was identified as a direct target of miR‑326. Additionally, overexpression of miR‑326 blocked the activation of the TGF‑β1/SMAD family member 3 (Smad3) signaling pathway by suppressing the expression of TGF‑β1 in ESCs from patients with IUA. The findings of the present study indicated that miR‑326 inhibited endometrial fibrosis by suppressing the TGF‑β1/Smad3 signaling pathway, suggesting that miR‑326 may be a prognostic biomarker and therapeutic target for IUA.