Fibroblast Collagen Research Articles

Epoxyeicosatrienoic acid administration or soluble epoxide hydrolase inhibition attenuates renal fibrogenesis in obstructive nephropathy.

Epoxyeicosatrienoic acids (EETs) are arachidonic acid metabolites with biological effects, including antiapoptotic, anti-inflammatory, and antifibrotic functions. Soluble epoxide hydrolase (sEH)-mediated hydrolysis of EETs to dihydroxyeicosatrienoic acids (DHETs) attenuates these effects. Recent studies have demonstrated that inhibition of sEH prevents renal tubulointerstitial fibrosis and inflammation in the chronic kidney disease model. Given the pathophysiological role of the EET pathway in chronic kidney disease, we investigated if administration of EET regioisomers and/or sEH inhibition will promote antifibrotic and renoprotective effects in renal fibrosis following unilateral ureteral obstruction (UUO). EETs administration abolished tubulointerstitial fibrogenesis, as demonstrated by reduced fibroblast activation and collagen deposition after UUO. The inflammatory response was prevented as demonstrated by decreased neutrophil and macrophage infiltration and expression of cytokines in EET-administered UUO kidneys. EET administration and/or sEH inhibition significantly reduced M1 macrophage markers, whereas M2 macrophage markers were highly upregulated. Furthermore, UUO-induced oxidative stress, tubular injury, and apoptosis were all downregulated following EET administration. Combined EET administration and sEH inhibition, however, had no additive effect in attenuating inflammation and renal interstitial fibrogenesis after UUO. Taken together, our findings provide a mechanistic understanding of how EETs prevent kidney fibrogenesis during obstructive nephropathy and suggest EET treatment as a potential therapeutic strategy to treat fibrotic diseases.NEW & NOTEWORTHY Epoxyeicosatrienoic acids (EETs) are cytochrome P-450-dependent antihypertensive and anti-inflammatory derivatives of arachidonic acid, which are highly abundant in the kidney and considered renoprotective. We found that EET administration and/or soluble epoxide hydrolase inhibition significantly attenuates oxidative stress, renal cell death, inflammation, macrophage differentiation, and fibrogenesis following unilateral ureteral obstruction. Our findings provide a mechanistic understanding of how EETs prevent kidney fibrogenesis during obstructive nephropathy and suggest that EET treatment may be a potential therapeutic strategy to treat fibrotic diseases.

Aging Fibroblasts Adversely Affect Extracellular Matrix Formation via the Senescent Humoral Factor Ependymin-Related Protein 1

Skin senescence is characterized by a decrease in extracellular matrix and the accumulation of senescent fibroblasts in the dermis, and their secretion of humoral factors. Ependymin-related protein 1 (EPDR1) is involved in abnormal fibroblast metabolism and collagen deposition, however, its relation to skin aging is unclear. We investigated whether and how EPDR1 is involved in age-related dermal deterioration. When young dermal fibroblasts and senescent cells were co-cultured in a semipermeable membrane separation system, the young fibroblasts showed decreased gene expression of collagen type I α1 chain (COL1A1) and elastin, and increased expression of matrix metalloproteinase (MMP)1 and MMP3. Senescence marker expression and EPDR1 production were increased in the culture medium of senescent cells. Treatment of young fibroblasts with recombinant EPDR1, enhanced matrix-related gene expression and suppressed COL1A1 expression, whereas EPDR1 knockdown had the opposite effects. EPDR1 gene and protein expression were increased in aged skin, compared to young skin. These results suggest that senescent cells affect nearby fibroblasts, in part through EPDR1 secretion, and exert negative effects on matrix production in the dermis. These results may lead to the discovery of potential candidate targets in the development of skin anti-aging therapies.

LOX-1 deficiency increases ruptured abdominal aortic aneurysm via thinning of adventitial collagen.

Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is a key mediator of inflammation and plays an important role in the pathogenesis of atherosclerosis. Conversely, LOX-1 deficiency has been shown to decrease inflammation and atherosclerosis, both of which have been proposed to contribute to abdominal aortic aneurysm (AAA) pathogenesis. However, the role of LOX-1 in AAA pathogenesis remains unknown. Here, we investigated the effects of Olr1 (which encodes LOX-1) deletion on angiotensin II (Ang II)-induced AAA in apolipoprotein E knockout (ApoE KO) mice to determine whether LOX-1 deficiency mitigates AAA development. To accomplish this, we used serial, non-invasive ultrasound assessment, which revealed that the incidence and expansion rate of AAA were similar regardless of Olr1 deletion. However, Olr1 deletion significantly increased severe AAAs, including ruptured AAAs resulting in death. Oil Red O staining of the harvested aortas showed that the extent of atheroma burden localized in aneurysmal lesions did not differ between LOX-1-deficient and control mice, suggesting that Olr1 deletion did not decrease atheroma burden in the aneurysmal wall. Further histopathological analysis revealed that aneurysmal lesions in LOX-1-deficient mice had fewer fibroblasts and myofibroblasts, as well as thinner adventitial collagen, although the degree of elastin fragmentation or disruption was similar between LOX-1-deficient and control mice. An in vitro study confirmed that the proliferation of adventitial fibroblasts collected from LOX-1-deficient mice was significantly attenuated despite Ang II stimulation. In conclusion, Olr1 deletion may not mitigate aneurysm development but rather increases the vulnerability of rupture by suppressing adventitial fibroblast proliferation and collagen synthesis.

In vitro biological activities and preliminary phytochemical screening of different extracts from Achillea sintenisii Hub- Mor

This study was designed to investigate in vitro biological activities and phytochemical composition of aqueous and ethanolic extracts from Achillea sintenisii Hub- Mor. (AS). To determine the chemical composition of AS extracts, phytochemical analyses were performed by using HPLC–ESI-Q-TOF-MS-MS. Afterwards, both extracts were investigated in terms of their effect on fibroblast proliferation, collagen synthesis, and hydrogen peroxide-induced damage. In addition to cell culture analysis, antibacterial, antioxidant, hyaluronidase inhibitory activities and total phenolic contents of the extracts were analyzed in cell-free systems. Our results demonstrated that the aqueous and ethanolic extracts did not show cytotoxic activity on fibroblasts, on the contrary, promoted fibroblast proliferation. Both AS extracts potently inhibited hyaluronidase activity and the inhibitory effect of ethanolic extract was comparable with the positive control, especially at high concentrations. The aqueous extract was the potent stimulator of collagen synthesis at 200 µg/mL concentration. Although the ethanolic extract showed antibacterial activity against all gram-positive bacteria, the aqueous extract was only effective against K. pneumoniae and B. subtilis. The ability of AS extracts, which have a rich phenolic compound content (≥50 mg GAE/g), to scavenge free radicals and protect fibroblasts against hydrogen peroxide-induced damage can be considered as a result of their antioxidant potential. Our findings scientifically support the widespread use of this plant, by demonstrating the pharmacological properties of the extracts.

The deubiquitinating enzyme USP37 promotes keloid fibroblasts proliferation and collagen production by regulating the c-Myc expression.

Previous research testifies that c-Myc may promote keloid fibroblast proliferation and collagen accumulation. Ubiquitin-specific peptidase 37 (USP37)-mediated deubiquitination and stabilisation of c-Myc are vital for lung cancer proliferation, while the potential role of USP37 in keloid fibroblasts is not investigated. Elevated USP37, c-Myc, and Collagen I content were detected in keloid tissue with RT-PCR or ELISA assay. USP37 over-expression plasmids or USP37 short hairpin RNAs (shRNAs) were transfected into keloid fibroblasts with Lipofectamine 3000 to decipher the role of USP37 in keloid fibroblasts. USP37 overexpression could promote the proliferation of keloid fibroblasts with increased c-Myc and Collagen I expression. On the other hand, USP37 shRNAs inhibited the proliferation of keloid fibroblasts with diminished c-Myc and Collagen I expression. It was worth noting that C-Myc overexpression promoted the proliferation of keloid fibroblasts inhibited by USP37 shRNAs with increasing Collagen I expression. All of these results demonstrate that USP37 could regulate c-Myc to promote the proliferation and collagen deposit of keloid fibroblasts, and USP37 could be targeted in future keloid therapy.

Hyaluronic Acid Gel Incorporating Curcumin-Phospholipid Complex Nanoparticles Prevents Postoperative Peritoneal Adhesion

Peritoneal adhesions following abdominal procedures remain a major surgical issue. This study aimed to evaluate the preventive effect of curcumin-soybean phosphatidylcholine (CUR-SPC) complex-loaded nanoparticles (NPs) embedded in hyaluronic acid (HA) gel. CUR-SPC complex, CUR-SPC NPs, and CUR-SPC-HA gel were fully characterized regarding particle size, zeta potential, morphology, XRD, FTIR, in-vitro release, and rheology. The in vivo efficacy was investigated in a rat model of cecum abrasion and sidewall defect. The optimized spherical-shaped CUR-SPC NPs had a high CUR loading with nanometric particle size (93 nm). CUR-SPC-HA gel showed a pseudoplastic behavior with a homogeneous distribution of CUR-SPC NPs and a sustained release profile over 3 weeks. The inhibitory effect of CUR-SPC-NP-HA gel on fibroblast proliferation and collagen synthesis was evidenced by histopathological (H&E and Masson trichrome staining) and immunohistochemical analyses (vimentin and collagen I expression). Thus, the proposed NP-gel hybrid system could be a promising postoperative anti-adhesion candidate, employing the advantages of CUR, SPC, and HA.

Oral mucositis on a chip: modeling induction by chemo- and radiation treatments and recovery

Oral mucositis (OM) is a debilitating complication affecting roughly 70% of head and neck cancer patients receiving chemotherapy and/or radiation treatment. No broadly effective preventative treatment for OM exists. Therefore, an in vitro model of cancer treatment-induced OM would aid studies into possible origins of the pathology and future drug targets to ameliorate it. In this study, we present a microfluidic oral mucosa triculture tissue construct consisting of a keratinocyte layer attached to a subepithelial fibroblast and endothelial cell-embedded collagen gel. To address the typically low stability of mucosal constructs in microfluidics, ruthenium-catalyzed photocrosslinking was implemented to strengthen the collagen gel and prevent the invasion of keratinocytes, thus maintaining tissue construct geometry and oral mucosa barrier function for over 18 d of culture. Next, the OM chip was exposed to cisplatin (day 10) and damaging radiation (day 11, ± cisplatin at day 10), mimicking damage from cancer therapy. Damage to and then recovery of the tissue layers and function were observed over days 11–18. Therefore, several important features of OM induction and resolution were modeled in microfluidic culture. The OM model on a chip allows for more sophisticated studies into mechanisms of OM and potential treatments.

Angiotensin II type 2 receptor prevents extracellular matrix accumulation in human peritoneal mesothelial cell by ameliorating lipid disorder via LOX‐1 suppression

Evidence suggests that intracellular angiotensin II type 1 receptor (AT1) contributes to peritoneal fibrosis (PF) under high glucose (HG)-based dialysates. It is generally believed that AT2 antagonisticly affects AT1 function. The aim of this study was to explore whether AT2 activation is beneficial for attenuating human peritoneal mesothelial cell (HPMC) injury due to HG. We treated a HPMC line with HG to induce extracellular matrix (ECM) formation. AT2 was increased and blocked using CGP42112A and AT2 siRNA. Lipid deposition was detected, signaling molecules associated with lectin-like oxidized lipoprotein receptor-1 (LOX-1) and ECM proteins were evaluated by real-time PCR and western blot. The results showed that HG led to AT2 inhibition in HPMCs, inhibition of AT2 further aggravated the expression of ECM proteins, including α-smooth muscle actin, fibroblast specific protein-1 and collagen I, while AT2 decreased the expression of ECM proteins, even during HG stimulation. Interestingly, there was a parallel change in lipid accumulation and ECM formation when AT2 was increased or depressed. Moreover, AT2-mediated decreased ECM production was associated with reduced lipid accumulation in HPMCs and depended on the downregulation of LOX-1. Further analysis showed that HG increased oxidized low-density lipoprotein (ox-LDL) deposition in HPMCs concomitant with an enhanced expression of ECM components, whereas blocking LOX-1 reversed ox-LDL deposition even in the presence of HG. This effect was also accompanied by the remission of ECM accumulation. Our results suggested that AT2 prevented ECM formation in HG-stimulated HPMCs by ameliorating lipid via LOX‐1 suppression.

Oxygen-Glucose Deprivation Promoted Fibroblast Senescence and Collagen Expression via IL11.

Cell senescence is one of the most important forms of injury induced by cardiovascular and other ischemic diseases. Fibroblasts are important participants in tissue repair after ischemic injury and the main source of IL11 secretion. However, the roles of oxygen–glucose deprivation (OGD) and IL11 in promoting fibroblast senescence and their regulatory mechanisms remain unclear. This study selected the NIH3T3 and L929 fibroblast cell lines as research objects. We found that OGD could induce the expression of p53, P16, p21, and collagen in fibroblasts. In the condition of OGD, when IL11 intervened, fibroblasts’ senescence and collagen expression were changed. Some studies have found that changes in kynurenine (KYN) metabolism are related to aging diseases, and indoleamine 2,3-dioxygenase 1 (IDO1) is a key rate-limiting enzyme in the KYN metabolic pathway. We found that KYN secretion decreased after OGD increased fibroblast senescence, and inhibition of IL11 promoted IDO1 and increased KYN secretion. These results suggest that OGD may promote fibroblast senescence and collagen expression via IL11 inhibition of the IDO1/KYN metabolic pathway. Therefore, the revealed mechanism of OGD-promoted fibroblast senescence could provide an effective theoretical basis for the clinical treatment of aging-related ischemic diseases.

Role of endothelial dysfunction in the severity of COVID‑19 infection (Review).

COVID-19 patients with severe infection have been observed to have elevated auto-antibodies (AAs) against angiotensin II receptor type 1 (AT1R) and endothelin (ET) 1 receptor type A (ETAR), compared with healthy controls and patients with favorable (mild) infection. AT1R and ETAR are G protein-coupled receptors, located on vascular smooth muscle cells, fibroblasts, immune and endothelial cells, and are activated by angiotensin II (Ang II) and ET1 respectively. AAs that are specific for these receptors have a functional role similar to the natural ligands, but with a more prolonged vasoconstrictive effect. They also induce the production of fibroblast collagen, the release of reactive oxygen species and the secretion of proinflammatory cytokines (including IL-6, IL-8 and TNF-α) by immune cells. Despite the presence of AAs in severe COVID-19 infected patients, their contribution and implication in the severity of the disease is still not well understood and further studies are warranted. The present review described the major vascular homeostasis systems [ET and renin-angiotensin-aldosterone system (RAAS)], the vital regulative role of nitric oxide, the AAs, and finally the administration of angiotensin II receptor blockers (ARBs), so as to provide more insight into the interplay that exists among these components and their contribution to the severity, prognosis and possible treatment of COVID-19.

Decreased mitochondrial function in UVA-irradiated dermal fibroblasts causes the insufficient formation of type I collagen and fibrillin-1 fibers

BackgroundDecreases of collagen fibers and the disappearance of oxytalan fibers are typical symptoms of photoaged skin. Although a low quality of mitochondria (MT) in photoaged skin cells has been observed, it is unknown whether the decreased quality of MT is responsible for the insufficient formation of dermal fibers. ObjectiveTo identify the role of mitochondrial quality in skin photoaging focusing on the formation of dermal fibers. MethodsType I collagen and fibrillin-1 fibers in normal human dermal fibroblasts (NHDFs) were observed by immunostaining. Type I collagen and fibrillin-1 proteins in NHDFs were quantified by ELISA. Mitochondrial quality was evaluated by measuring levels of intracellular ATP and MITOL, which regulate mitochondrial quality. ResultsUVA-irradiated NHDFs formed insufficient type I collagen and fibrillin-1 fibers and had a decreased ratio of extracellular versus intracellular levels of those proteins. Although expression levels of motor proteins that transport those proteins intracellularly were not affected by UVA, intracellular ATP levels, which is the driving force of motor proteins, were decreased by UVA along with decreased MITOL protein. Knockdown of MITOL in NHDFs decreased the level of intracellular ATP and caused the insufficient formation of type I collagen and fibrillin-1 fibers due to interfering with the secretion of those proteins. ConclusionThese results indicate that a low quality of MT with ATP depletion in dermal fibroblasts caused by irradiation with UVA induces the insufficient formation of type I collagen and fibrillin-1 fibers due to the decreased extracellular secretion of those proteins.

Molecular mechanism of benign biliary stricture inhibition by rosiglitazone-activated peroxisome proliferator-activated receptor gamma.

The aim of this study was to investigate whether rosiglitazone-activated peroxisome proliferator-activated receptor gamma can inhibit the occurrence of benign biliary stricture and further elucidate the relevant molecular signaling mechanism. The primary cultured rat biliary fibroblasts following experiments were performed using within the fifth generation cells, which were separated from the bile ducts of Sprague-Dawley rats. The primary cultured rat biliary fibroblasts were co-cultured with 10 ng/mL transforming growth factor-beta 1 for stimulating collagen formation. Competent cells were transfected with siRNA that specifically target Smad3 or connective tissue growth factor to inhibit the expression of the corresponding proteins. The cells were incubated with 10 μmol/L rosiglitazone to activate peroxisome proliferator-activated receptor gamma. The cells were incubated with 10 μmol/L GW9662 in the pretreatment session to inactivate peroxisome proliferator-activated receptor gamma. ELISA was used to determine the levels of connective tissue growth factor and type I collagen in the cell supernatant. Western blotting was used to detect the levels of intracellular p-Smad3/t-Smad3. Rosiglitazone-activated peroxisome proliferator-activated receptor gamma inhibited the secretion of type I collagen induced by transforming growth factor-beta 1. Peroxisome proliferator-activated receptor gamma inhibitor GW9662 could significantly reverse the rosiglitazone-triggered inhibition of transforming growth factor-beta 1-induced type I collagen secretion by suppressing peroxisome proliferator-activated receptor gamma activation (p<0.01). Furthermore, we also found that the activation of peroxisome proliferator-activated receptor gamma was accompanied by the inhibition of transforming growth factor-beta 1-induced Smad3 phosphorylation (p<0.01), increased connective tissue growth factor expression (p<0.01), and production of type I collagen (p<0.01), all of which effects elicited by rosiglitazone could be reversed by peroxisome proliferator-activated receptor gamma inhibitor GW9662. Peroxisome proliferator-activated receptor gamma activated by rosiglitazone inhibits the transforming growth factor-beta1 -induced phosphorylation of Smad3 and the increased connective tissue growth factor expression as well as inhibits the secretion of type I collagen in biliary fibroblasts.

The efficacy of captopril and 5-fluorouracil combination in the proliferation and collagen deposition of keloid fibroblast

Keloid is a benign fibroproliferative tissue growth that exceeds the initial wound margins. Captopril has been tested in vitro to reduce fibroblast proliferation and collagen deposition; thus, it has potential for use in the treatment of keloids. Meanwhile, 5‐fluorouracil (5‐FU) has already been used in keloid management. This study aimed to determine the efficacy of the combination of captopril and 5‐FU in keloid fibroblast cultures. Keloid tissues were cultured up to passages 4–7. The study consisted of a control group, captopril in various concentrations (10‐2, 10‐3, 10‐4, and 10‐5 mol/L), 5‐FU 1 mg/mL and a combination of captopril at various concentrations with 5‐FU 1 mg/mL. After 144 hours of treatment, fibroblast proliferation and collagen deposition were measured. The study showed a significant decrease in the mean index of fibroblast proliferation and collagen deposition in the group receiving captopril in various concentrations (10‐2, 10‐3, 10‐4, and 10‐5 mol/L) and the 5‐FU group against the control group (p&lt;0.05). In the combined‐dose group, captopril at a concentration of 10‐2 mol/L and 5‐FU showed a significant reduction in fibroblast proliferation and collagen deposition compared to the 5‐FU group and the captopril at the same dose (p&lt;0.05). In conclusion, the combination of captopril 10‐2 mol/L and 5‐FU 1 mg/mL is better at reducing fibroblast proliferation and collagen deposition in keloid fibroblast cultures than captopril or 5‐FU as a single therapeutic agent.

Enhanced anti-wrinkle activity of adlay bran fermented with Lactobacillus brevis MJM60390.

The aim of this study was to screen the lactic acid bacteria for fermentation of adlay bran and evaluate the anti-wrinkle effect of fermented and non-fermented adlay bran. Adlay bran was fermented with candidate LAB and extracted with 70% ethanol. The extracts from LAB-fermented adlay bran and non-fermented adlay bran were evaluated for the anti-wrinkle effects by measuring the hyaluronan, collagen, and elastin production in cells using ELISA kit. The molecular anti-wrinkle mechanism was investigated by RT-qPCR. Furthermore, the antioxidant activity, total phenolic and flavonoid content were also determined. Among the tested LAB, Lactobacillus brevis MJM60390 was selected for the highest glycosidase activity. Both extracts from adlay bran (NFAB) and L. brevis MJM60390-fermented adlay bran (LBFAB) showed anti-wrinkle effect, and LBFAB showed higher activity. Compared with control, hyaluronan production was increased by 24.73% and 59.38%, collagen production was increased by -13.08% and 34.19%, and the elastin production was increased by 29.78% and 53.73% by NFAB and LBFAB treatment, respectively. Investigation on the mRNA expression showed that LBFAB upregulated the expression of Has 2 and Has 3 and downregulate HYAL1 and HYAL2. LBFAB also upregulated the mRNA expression of COL1A1, COL1A2, ELN and inhibited the expression of collagenase and elastase. However, not all of these genes were regulated by NFAB. Furthermore, the antioxidant activity was significantly increased after fermentation, and the content of the phenolic and flavonoid compounds also increased in the LBFAB. In this study, we demonstrated that fermentation of adlay bran with L. brevis MJM60390 enhanced the anti-wrinkle activity through increasing the hyaluronan synthesis in keratinocytes and improving collagen and elastin production in dermal fibroblasts.

Laser-assisted nanoparticle delivery to promote skin absorption and penetration depth of retinoic acid with the aim for treating photoaging

Retinoic acid (RA) is an approved treatment for skin photoaging induced by ultraviolet (UVA). Topically applied RA is mainly located in the stratum corneum (SC) with limited diffusion into the deeper strata. A delivery system capable of facilitating dermal delivery and cellular internalization for RA is critical for a successful photoaging therapy. Two delivery approaches, namely nanoparticles and laser ablation, were combined to improve RA’s absorption efficacy and safety. The nanoparticle absorption enhancement by the lasers was compared between full-ablative (Er:YAG) and fractional (CO2) modalities. We fabricated poly-L-lactic acid (PLA) and PLA/poly(lactic-co-glycolic acid) (PLGA) nanoparticles by an emulsion-solvent evaporation technique. The mean size of PLA and PLA/PLGA nanocarriers was 237 and 222 nm, respectively. The RA encapsulation percentage in both nanosystems was > 96 %. PLA and PLA/PLGA nanocarriers promoted RA skin deposition by 5- and 3-fold compared to free control. The ablative lasers further enhanced the skin deposition of RA-loaded nanoparticles, with the full-ablative laser showing greater permeation enhancement than the fractional mode. The skin biodistribution assay evaluated by confocal and fluorescence microscopies demonstrated that the laser-assisted nanoparticle delivery achieved a significant dermis and follicular accumulation. The cell-based study indicated a facile uptake of the nanoparticles into the human dermal fibroblasts. The nanoparticulate RA increased type I collagen and elastin production in the UVA-treated fibroblasts. A reduction of matrix metalloproteinase (MMP)-1 was also highlighted in the photoaging cells. The calculation of therapeutic index (TI) by multiplying collagen/elastin elevation percentage and skin deposition predicted better anti-photoaging performance in Er:YAG laser-assisted nanoparticle delivery than CO2 laser. Nanoencapsulation of RA decreased the cytotoxicity against skin fibroblasts. In vivo skin tolerance test on a nude mouse showed less skin damage after topical application of the nanoparticles than free RA. Our results hypothesized that the laser-mediated nanoparticle delivery provided an efficient and safe use for treating photoaging.

Histologic Evaluation of the Effects of Folinic Acid Chitosan Hydrogel and Botulinum Toxin A on Wound Repair of Cleft Lip Surgery in Rats.

The aim of the present study was to compare the effects of folinic acid chitosan hydrogel and botulinum toxin A on the wound repair of cleft lip surgery in rat animal models. Cleft lip defects were simulated by triangular incisions in the upper lip of 40 Wistar rats. Then, the rats were randomly assigned to four groups: control (CTRL), chitosan hydrogel (CHIT), and folinic acid chitosan hydrogel (FOLCHIT), in which the wounds were covered by a gauze pad soaked in normal saline, chitosan hydrogel, and folinic acid chitosan hydrogel, respectively for 5 min immediately after closure; and botulinum toxin A (BOT) with the injection of 3 units of botulinum toxin A in the wound region. Fibroblast proliferation, collagen deposition, inflammatory cell infiltration, neovascularization, and epithelial proliferation and each parameter were rated on days 14 and 28. Statistical analysis was performed by Kolmogorov-Smirnov test, Shapiro-Wilk test, Kruskal-Wallis, and post-hoc tests (α = 0.05). The mean score for fibroblast proliferation was significantly higher in the FOLCHIT group compared with the BOT group at days 14 and 28 (p < 0.001, p = 0.012, respectively). At day 28, collagen deposition was significantly higher in the FOLCHIT group compared with the BOT group (p = 0.012). No significant difference was observed between the inflammatory infiltration of the study groups at the two time points (p = 0.096 and p = 1.000, respectively). At day 14, vascular proliferation of group FOLCHIT was significantly higher than groups CTRL and CHIT (p = 0.001 and p = 0.006, respectively). The epithelial proliferation in the FOLCHIT group was significantly higher than groups CHIT and CTRL at day 14 (p = 0.006 and p = 0.001, respectively) and day 28 (p = 0.012). In simulated lip cleft defects, topical application of folinic acid induces faster initial regeneration by higher inflammation and cellular proliferation, at the expense of a higher tendency for scar formation by slightly higher fibroblast proliferation and collagen deposition. While injection of botulinum toxin A provides less fibroblast proliferation and collagen deposition, and thus lower potential for scar formation compared with the folinic acid group. Therefore, in wounds of the esthetic zone, such as cleft lip defects, the application of botulinum toxin A shows promising results.

Chitosan/Hyaluronic Acid/MicroRNA-21 Nanoparticle-Coated Smooth Titanium Surfaces Promote the Functionality of Human Gingival Fibroblasts.

PurposeForming a compact biological seal between the gingiva and the implant interface around the percutaneous parts of an implant is one of the key issues in preventing peri-implantitis.MethodsIn this study, since microRNA-21 (miR-21) has been approved to promote fibroblast proliferation and collagen formation in skin fibrosis, we prepared miR-21-loaded chitosan (CS)/tripolyphosphate (TPP)/hyaluronic acid (HA) nanoparticles (CTH NPs) and cross-linked them to smooth Ti surfaces with 0.2% gel solution for reverse transfection, after which isolated human gingival fibroblasts were cultured on the miR-21-functionalized Ti substrates.ResultsAn optimal CS:TPP:HA ratio (1:0.15:0.1) and N/P ratio (20:1) were chosen to produce appropriate nanoparticles. Finally, the CTH/miR-21 nanoparticle-coated smooth Ti surfaces demonstrated increased fibroblast adhesion, proliferation and expression of extracellular matrix-related genes along with similar cytotoxicity and cell spreading on the miR-21-functionalized Ti surface and the unmodified smooth Ti surface.ConclusionThe chitosan-based nanoparticles might be an efficient nonviral miRNA vector to form a stable biological seal in percutaneous areas of Ti for clinical use.

A novel lncRNA FPASL regulates fibroblast proliferation via the PI3K/AKT and MAPK signaling pathways in hypertrophic scar.

Hypertrophic scar is a problem for numerous patients, especially after burns, and is characterized by increased fibroblast proliferation and collagen deposition. Increasing evidence demonstrates that lncRNAs contribute to the development and progression of various diseases. However, the function of lncRNAs in hypertrophic scar formation remains poorly characterized. In this study, a novel fibroblast proliferation-associated lncRNA, named lncRNA FPASL (MSTRG.389905.1), which is mainly localized in the cytoplasm, is found to be downregulated in hypertrophic scar, as detected by lncRNA microarray and qRT-PCR. The full-length FPASL is characterized and further investigation confirms that it has no protein-coding potential. FPASL knockdown in fibroblasts triggers fibroblast proliferation, whereas overexpression of FPASL directly attenuates the proliferation of fibroblasts. Furthermore, target genes of the differentially expressed lncRNAs in hypertrophic scars and the matched adjacent normal tissues are enriched in fibroblast proliferation signaling pathways, including the PI3K/AKT and MAPK signaling pathways, as determined by GO annotation and KEGG enrichment analysis. We also demonstrate that knockdown of FPASL activates the PI3K/AKT and MAPK signaling pathways, and specific inhibitors of the PI3K/AKT and MAPK signaling pathways can reverse the proliferation of fibroblasts promoted by FPASL knockdown. Our findings contribute to a better understanding of the role of lncRNAs in hypertrophic scar and suggest that FPASL may act as a potential novel therapeutic target for hypertrophic scar.

Radiation-induced FAP + fibroblasts are involved in keloid recurrence after radiotherapy.

Background: Keloid scars (KSs), which are composed of abnormal hyperplastic scar tissue, form during skin wound healing due to excessive fibroblast activation and collagen secretion. Although surgical resection and radiation therapy are used to prevent recurrence, KS recurrence rates range from 15 to 23%, and the underlying mechanism is unclear. Methods: To elucidate the mechanism of keloid recurrence, we established a PDX model and the grafts remained for over 20 weeks after transplantation on the bilateral backs of the NCG mice. Results: RNA-seq revealed that KS tissue gene expression was highly consistent before and after transplantation. Then, one side of the KS graft was irradiated with electron beam therapy (10 Gy), significant increases in vimentin and fibroblast activation protein alpha (FAP) expression were observed after irradiation and were accompanied by severe microvascular destruction. Surprisingly, 4 weeks after irradiation, significantly increased recurrence was observed with increased FAP + tissue and cell cycle regulator expression, resulting in a remarkable altered graft volume. Moreover, irradiation-induced FAP upregulation markedly facilitated radiation resistance and increased cell cycle progression, decreased senescence, and increased energy production. Conclusion: Our findings revealed that irradiation causes increased abundance of FAP + cells, which was associated with cell proliferation and delayed cellular senescence, accompanied by ATP production.

Direct three-dimensional printed egg white hydrogel wound dressing promotes wound healing with hitching adipose stem cells.

Current wound dressing based on hydrogel offers a promising way to accelerate the healing process, yet great challenges remain in the development of a highly integrated and efficient platform with the combination of therapeutic biomolecules and stem cells. Herein, a natural hydrogel wound dressing from egg white can be conveniently obtained by feasible physical crosslinking, the prepared hydrogel dressing features interconnected microporous channels, direct 3D printing, cytocompatibility, and intrinsic biomolecules to advance cell behavior. The 3D printed egg white hydrogels promote the adhesion and proliferation of adipose-derived stem cells (ASCs) without obvious cytotoxicity. In addition, this integrated hydrogel platform accompanied with adipose-derived stem cells accelerates wound healing through the enhancement of fibroblast proliferation, angiogenesis, and collagen rearrangement in the wound bed. The egg white hydrogel provides an effective wound caring product possessing low cost, easy availability along with ready manufacturing, and advanced therapeutic effect, which may be extended for the management of chronic or other complicated wounds.