Optimization of the extraction conditions and dermal toxicity of oil body fused with acidic fibroblast growth factor (OLAF).

INTRODUCTION: Oil body (OB), a subcellular organelle that stores oil in plant seeds, is considered a new transdermal drug delivery system. With the increasing understanding of the OB and its main protein (oleosin), numerous studies have been conducted on OB as "carrier" for the expression of exogenous proteins. In our previous study, oil body fused with aFGF (OLAF) was obtained using a plant oil body expression system that had been preliminarily proven to be effective in accelerating the healing of skin wounds. However, no dermal toxicological information on OLAF is available. OBJECTIVE: To ensure the dermal safety of OLAF, a series of tests (the acute dermal toxicity test, 21-day repeat dermal toxicity test, dermal irritation test and skin sensitisation test) were conducted after optimising the extraction protocol of OLAF. MATERIALS AND METHODS: To improve the extraction rate of OLAF, response surface methodology (RSM) was first employed to optimise the extraction conditions. Then, Wistar rats were exposed to OLAF (400 mg·kg-1 body weight) in two different ways (6 hours/time for 24 hours and 1 time/day for 21 days) to evaluate the acute dermal toxicity and 21-day repeated dermal toxicity of OLAF. In the acute dermal toxicity test, clinical observations were conducted to evaluate the toxicity, behaviour, and health of the animals for 14 consecutive days. Similarly, the clinical signs, body weight, haematological and biochemical parameters, histopathological changes and other indicators were also detected during the 21 days administration. For the dermal irritation test, single and multiple doses of OLAF (125 mg·kg-1 body weight) were administered to albino rabbits for 14 days (1 time/day). The irritation reaction on the skin of each albino rabbit was recorded and scored. Meanwhile, skin sensitisation to OLAF was conducted using guinea pigs for a period of 28 days. RESULTS: Suitable extraction conditions for OLAF (PBS concentration 0.01, pH of PBS 8.6, solid-liquid ratio 1:385 g·mL-1) were obtained using RSM. Under these conditions, the extraction rate and particle size of OLAF were 7.29% and 1290 nm, respectively. In the tests of acute dermal toxicity and 21-day repeated dermal toxicity, no mortality or significant differences were observed in terms of clinical signs, body weight, haematological parameters, biochemical parameters and anatomopathological analysis. With respect to the dermal irritation test and skin sensitisation test, no differences in erythema, oedema or other abnormalities were observed between treatment and control groups on gross and histopathological examinations. CONCLUSIONS: The results of this study suggest that OLAF does not cause obvious toxicity, skin sensitisation or irritation in animals.

Fibroblast growth factor 1 ameliorates adipose tissue inflammation and systemic insulin resistance via enhancing adipocyte mTORC2/Rictor signal.

Obesity-induced activation and proliferation of resident macrophages and infiltration of circulating monocytes in adipose tissues contribute to adipose tissue inflammation and insulin resistance. These effects further promote the development of metabolic syndromes, such as type 2 diabetes, which is one of the most prevalent health conditions severely threatening human health worldwide. Our study examined the potential molecular mechanism employed by fibroblast growth factor 1 (FGF1) to improve insulin sensitivity. The leptin receptor-deficient obese mice (db/db) served as an insulin-resistant model. Our results demonstrated that FGF1-induced amelioration of insulin resistance in obese mice was related to the decreased levels of pro-inflammatory adipose tissue macrophages (ATMs) and plasma inflammatory factors. We found that FGF1 enhanced the adipocyte mTORC2/Rictor signalling pathway to inhibit C-C chemokine ligand 2 (CCL2) production, the major cause of circulating monocytes infiltration, activation and proliferation of resident macrophages in adipose tissues. Conversely, these alleviating effects of FGF1 were substantially abrogated in adipocytes with reduced expression of mTORC2/rictor. Furthermore, a model of adipocyte-specific mTORC2/Rictor-knockout (AdRiKO) obese mice was developed to further understand the in vitro result. Altogether, these results demonstrated adipocyte mTORC2/Rictor was a crucial target for FGF1 function on adipose tissue inflammation and insulin sensitivity.

Hypothalamic perineuronal net assembly is required for sustained diabetes remission induced by fibroblast growth factor 1 in rats.

We recently showed that perineuronal nets (PNNs) enmesh glucoregulatory neurons in the arcuate nucleus (Arc) of the mediobasal hypothalamus (MBH)1, but whether these PNNs play a role in either the pathogenesis of type 2 diabetes (T2D) or its treatment remains unclear. Here we show that PNN abundance within the Arc is markedly reduced in the Zucker diabetic fatty (ZDF) rat model of T2D, compared with normoglycaemic rats, correlating with altered PNN-associated sulfation patterns of chondroitin sulfate glycosaminoglycans in the MBH. Each of these PNN-associated changes is reversed following a single intracerebroventricular (icv) injection of fibroblast growth factor 1 (FGF1) at a dose that induces sustained diabetes remission in male ZDF rats. Combined with previous work localizing this FGF1 effect to the Arc area2-4, our finding that enzymatic digestion of Arc PNNs markedly shortens the duration of diabetes remission following icv FGF1 injection in these animals identifies these extracellular matrix structures as previously unrecognized participants in the mechanism underlying diabetes remission induced by the central action of FGF1.

Bioactive multi-engineered hydrogel offers simultaneous promise against antibiotic resistance and wound damage.

Wound healing is a complex process involved in repairing tissue damage and preventing infection. However, there is a lack of appropriate treatment solutions that can simultaneously promote tissue repair and protect againstbacteria, especially antibiotic-resistant bacteria. In this study, we have developed an injectable hydrogel encapsulating acidic fibroblast growth factor (aFGF) and bacteriophage, termed as ABgel, for combating antibiotic-resistant bacteria and enhancing wound regeneration. ABgel is composed of oxidized sodium alginate (OSA), gelatin and hyaluronic acid (HA), and can rapidly form hydrogel with an elastic modulus of 13 kPa, which mimics the skin tissues. In addition, ABgel can effectively load and stabilize bacteriophage and aFGF, allowing for preventing bacterial infections and improving regeneration of damaged dermal tissues. In vitro studies demonstrate that ABgel exhibits enormous antibacterial activity against antibiotic-resistant E. coli and enhanced angiogenetic activity. Importantly, ABgel can promote skin regeneration and prevent bacterial infections in mice, thereby promoting wound healing process. Therefore, ABgel represents a decent bioactive engineered hydrogel dressing with a broad application potential.

Transcriptomic analysis links diverse hypothalamic cell types to fibroblast growth factor 1-induced sustained diabetes remission.

In rodent models of type 2 diabetes (T2D), sustained remission of hyperglycemia can be induced by a single intracerebroventricular (icv) injection of fibroblast growth factor 1 (FGF1), and the mediobasal hypothalamus (MBH) was recently implicated as the brain area responsible for this effect. To better understand the cellular response to FGF1 in the MBH, we sequenced >79,000 single-cell transcriptomes from the hypothalamus of diabetic Lepob/ob mice obtained on Days 1 and 5 after icv injection of either FGF1 or vehicle. A wide range of transcriptional responses to FGF1 was observed across diverse hypothalamic cell types, with glial cell types responding much more robustly than neurons at both time points. Tanycytes and ependymal cells were the most FGF1-responsive cell type at Day 1, but astrocytes and oligodendrocyte lineage cells subsequently became more responsive. Based on histochemical and ultrastructural evidence of enhanced cell-cell interactions between astrocytes and Agrp neurons (key components of the melanocortin system), we performed a series of studies showing that intact melanocortin signaling is required for the sustained antidiabetic action of FGF1. These data collectively suggest that hypothalamic glial cells are leading targets for the effects of FGF1 and that sustained diabetes remission is dependent on intact melanocortin signaling.

Combined treatment with ultrasound-targeted microbubble destruction technique and NM-aFGF-loaded PEG-nanoliposomes protects against diabetic cardiomyopathy-induced oxidative stress by activating the AKT/GSK-3ß1/Nrf-2 pathway.

The present study sought to investigate the effect of non-mitogenic acidic fibroblast growth factor (NM-aFGF) loaded PEGylated nanoliposomes (NM-aFGF-PEG-lips) combined with the ultrasound-targeted microbubble destruction (UTMD) technique on modulating diabetic cardiomyopathy (DCM)and the mechanism involved. Animal studies showed that the diabetes mellitus (DM) group exhibited typical myocardial structural and functional changes of DCM. The indexes from the transthoracic echocardiography showed that the left ventricular function in the NM-aFGF-PEG-lips + UTMD group was significantly improved compared with the DM group. Histopathological observation further confirmed that the cardiomyocyte structural abnormalities and mitochondria ultrastructural changes were also significantly improved in the NM-aFGF-PEG-lips + UTMD group compared with DM group. The cardiac volume fraction (CVF) and apoptosis index in the NM-aFGF-PEG-lips + UTMD group decreased to 10.31 ± 0.76% and 2.16 ± 0.34, respectively, compared with those in the DM group (CVF = 21.4 ± 2.32, apoptosis index = 11.51 ± 1.24%). Moreover, we also found significantly increased superoxide dismutase (SOD) activity and glutathione peroxidase (GSH-Px) activity as well as clearly decreased lipid hydroperoxide levels and malondialdehyde (MDA) activity in the NM-aFGF-PEG-lips + UTMD group compared with those in the DM group (p < .05). Western blot analysis further revealed the highest level of NM-aFGF, p-AKT, p-GSK-3ß1, Nrf-2, SOD2 and NQO1 in the NM-aFGF-PEG-lips + UTMD group. This study confirmed using PEGylated nanoliposomes combined with the UTMD technique can effectively deliver NM-aFGF to the cardiac tissue of diabetic rats. The NM-aFGF can then inhibit myocardial oxidative stress damage due to DM by activating the AKT/GSK/Nrf-2 signaling pathway, which ultimately improved the myocardial structural and functional lesions in diabetic rats.

FGF1 inhibits H2O2-induced mitochondrion-dependent apoptosis in H9c2 cells.

The goal of this research was to reveal the protective effect and mechanism of fibroblast growth factor-1 (FGF1) on oxidative stress injury of H9c2 cells induced by hydrogen peroxide (H2O2). The effects of various concentrations of H2O2 and FGF1 on the activity of H9c2 cells were analyzed by Real Time Cell Analysis (RTCA). The content of ROS, calcium ion, mitochondrial membrane potential and apoptosis were detected by fluorescence probe, the mRNA expression of Bcl-2, Bax and Caspase-3 were detected by real-time PCR to evaluate whether FGF1 has ability to resist the apoptosis of cardiomyocytes caused by oxidative damage. The results showed that the proliferation of H9c2 cells could be inhibited after being treated with 200 µM H2O2 for 12 h, and 100 µg/ml FGF1 could increase the proliferation rate of H9c2 cells, mitochondrial membrane potential and the mRNA expression of Bcl-2, and reduce the ROS accumulation, the level of apoptosis, the content of intracellular calcium and the mRNA expression of Bax and Caspase-3 caused by H2O2. The results showed that FGF1 could regulate oxidative stress by improving mitochondrial function and inhibit the H2O2-induced apoptosis in H9c2 cells.

Topical recombinant human acidic fibroblast growth factor: An effective therapeutic agent for facemask wearing-induced pressure sores.

Protecting health care workers is crucial during coronavirus disease 2019 pandemic and facemask wearing is considered an effective measure to prevent severe acute respiratory syndrome coronavirus 2 infection. However, long-time use of a facemask can cause pressure sores on the ears and nose bridge and increase the risk of infection. The topical recombinant human acidic fibroblast growth factor (rh-aFGF) was used to cure pressure sores for health care workers at Zhongfaxincheng campus of Tongji Hospital. The results from a small sample size survey conducted in Zhongfaxincheng campuses of Tongji Hospital showed that treatment with topical rh-aFGF could significantly inhibit the progression of pressure sores and accelerate the wound healing with no apparent ill-effects. Therefore, we propose that topical rh-aFGF is an effective therapeutic agent for facemask wearing-induced pressure sores and worth of popularizing and applying.

Fibroblast growth factor 1 ameliorates diabetes-induced splenomegaly via suppressing inflammation and oxidative stress.

Type-2 diabetes (T2D) is a common metabolic disorder, which causes several physiological and pathological complications. Spleen is regarded as an important organ, which regulates immune system and iron metabolism in the body. Precious few studies have been conducted to explore the pathological and deleterious roles of diabetes on spleen. In our current study, we have explored and confirmed the pathological effects of diabetes on spleen in db/db experimental mice model. In our current study, 0.5 mg/kg fibroblast growth factor 1 (FGF1) dose was intraperitoneally administrated to db/db mice. We found that diabetes evidently induced spleen enlargement and fibrosis progression in the db/db mice. Additionally, our studies demonstrate that iron has hugely deposited in the spleen in db/db mice. Several studies have documented that diabetes largely disrupts the inflammatory cells distribution, immune homeostasis, proliferation and oxidative stress with the down-regulation of anti-inflammatory cytokines and antioxidant activities. Moreover, we have observed that FGF1 administration significantly reversed the deleterious effect of diabetes on spleen enlargement and dysfunction. In summary, these substantial findings clearly demonstrate that diabetes plays deleterious roles in maintaining the spleen structure and functions. Therefore, our investigations suggest that FGF1 can effectively prevent diabetes-mediated splenomegaly progression.

Central and Peripheral Administration of Fibroblast Growth Factor 1 Improves Pancreatic Islet Insulin Secretion in Diabetic Mouse Models.

Fibroblast growth factor 1 (FGF1) has been shown to reverse hyperglycemia in diabetic rodent models through peripheral and central administration routes. Previous studies demonstrated that insulin is required for central and peripheral FGF1 metabolic improvements; however, it is unknown if FGF1 targets insulin secretion at the islet level. Here we show for the first time that FGF1 increases islet insulin secretion in diabetic mouse models. FGF1 was administered via a single intracerebroventricular or multiple subcutaneous injections to leptin receptor-deficient (db/db), diet-induced obese, and control mice; pancreatic islets were isolated 7 days later for analysis of insulin secretion. Central and peripheral FGF1 significantly lowered blood glucose in vivo and increased ex vivo islet insulin secretion from diabetic, but not control, mice. FGF1 injections to the cisterna magna mimicked intracerebroventricular outcomes, pointing to a novel therapeutic potential. Central effects of FGF1 appeared dependent on reductions in food intake, whereas peripheral FGF1 had acute actions on islet function prior to significant changes in food intake or blood glucose. Additionally, peripheral, but not central, FGF1 increased islet ß-cell density, suggesting that peripheral FGF1 may induce long-term changes in islet structure and function that are not present with central treatment.

A combination of mupirocin and acidic fibroblast growth factor for nipple fissure and nipple pain in breastfeeding women: protocol for a randomised, double-blind, controlled trial.

INTRODUCTION: Nipple fissure and nipple pain are common complaints among breastfeeding mothers. Studies found that mupirocin was effective in preventing and treating infections of damaged nipple and nipple pain. Acidic fibroblast growth factor (aFGF) plays an important role in wound healing. However, current evidence on the efficacy and safety of mupirocin plus aFGF for nipple fissure and nipple pain in breastfeeding women is inconclusive due to the lack of well-designed randomised controlled trials on this topic. The purpose of this study is to test the hypothesis that mupirocin plus aFGF is more effective than mupirocin alone for nipple fissure and nipple pain in breastfeeding women. METHODS AND ANALYSIS: This study is a randomised, double-blind, single-centre, parallel-group clinical trial. A total of 120 breastfeeding women with nipple fissure and nipple pain will be randomly assigned to either mupirocin plus aFGF group or mupirocin plus placebo group according to a computer-generated random allocation sequence. The treatment period lasts 14 days. The primary outcome is nipple pain intensity measured by the Visual Analogue Scale on day 14 during the treatment period. Secondary outcome measures include time to complete nipple pain relief, changes in the Nipple Trauma Score, time to complete healing of nipple trauma, quality of life measured by the Maternal Postpartum Quality of Life (MAPP-QOL) Questionnaire, the frequency of breast feeding, the rate of breastfeeding discontinuation, weight change in infants and adverse events. ETHICS AND DISSEMINATION: The study has gained approval from the Ethics Review Committee of Tianjin Central Hospital of Gynaecology Obstetrics on 22 January 2018 (approval no. 2018KY001). We plan to publish our research findings in a peer-reviewed academic journal and disseminate these findings in international conferences. This study has been registered with the Chinese Clinical Trial Registry. TRIAL REGISTRATION NUMBER: ChiCTR1800017248.

Enhanced tendon-bone healing with acidic fibroblast growth factor delivered in collagen in a rabbit anterior cruciate ligament reconstruction model.

BACKGROUND: The objective of the present study was to investigate the effectiveness of acidic fibroblast growth factor delivered in collagen (aFGF/collagen) for promoting tendon-bone interface healing after anterior cruciate ligament (ACL) reconstruction in rabbits. METHODS: ACL reconstructions were performed in the right hind limbs of New Zealand rabbits. Each left long digital extensor tendon was harvested as an autograft, and collagen incorporating different concentrations of aFGF or same amount of collagen alone was applied at the tendon-bone interface after ACL reconstruction. The control group underwent ACL reconstruction only. There were high and low aFGF/collagen groups, collagen alone group, and control group (n = 21 rabbits per group). Histological and biomechanical analyses were performed at 4, 8, and 12 weeks postoperatively to evaluate the effect of aFGF/collagen on tendon-bone interface healing. RESULTS: Results of biomechanical tests showed that at both 8 and 12 weeks postoperatively, the elastic modulus and stiffness in both the high and low aFGF/collagen treatment groups were significantly higher than those in the control group and collagen alone group, with that in the high aFGF/collagen concentration group being the highest. Histological analysis showed that at 8 weeks, tightly organized Sharpey-like fibers were observed in both aFGF/collagen groups with new bone growth into the tendon in the high concentration group. At 12 weeks postoperatively, a fibrocartilage transition zone was observed in the bone tunnels in both aFGF/collagen groups, especially in the high aFGF/collagen group. CONCLUSION: Application of the aFGF/collagen composite could enhance early healing at the tendon-bone interface after ACL reconstruction, especially with the use of a high aFGF/collagen concentration.

Novel multi-drug delivery hydrogel using scar-homing liposomes improves spinal cord injury repair.

Proper selection and effective delivery of combination drugs targeting multiple pathophysiological pathways key to spinal cord injury (SCI) hold promise to address the thus far scarce clinical therapeutics for improving recovery after SCI. In this study, we aim to develop a clinically feasible way for targeted delivery of multiple drugs with different physiochemical properties to the SCI site, detail the underlying mechanism of neural recovery, and detect any synergistic effect related to combination therapy. Methods: Liposomes (LIP) modified with a scar-targeted tetrapeptide (cysteine-alanine-glutamine-lysine, CAQK) were first constructed to simultaneously encapsulate docetaxel (DTX) and brain-derived neurotrophic factor (BDNF) and then were further added into a thermosensitive heparin-modified poloxamer hydrogel (HP) with affinity-bound acidic fibroblast growth factor (aFGF-HP) for local administration into the SCI site (CAQK-LIP-GFs/DTX@HP) in a rat model. In vivo fluorescence imaging was used to examine the specificity of CAQK-LIP-GFs/DTX binding to the injured site. Multiple comprehensive evaluations including biotin dextran amine anterograde tracing and magnetic resonance imaging were used to detect any synergistic effects and the underlying mechanisms of CAQK-LIP-GFs/DTX@HP both in vivo (rat SCI model) and in vitro (primary neuron). Results: The multiple drugs were effectively delivered to the injured site. The combined application of GFs and DTX supported neuro-regeneration by improving neuronal survival and plasticity, rendering a more permissive extracellular matrix environment with improved regeneration potential. In addition, our combination therapy promoted axonal regeneration via moderation of microtubule function and mitochondrial transport along the regenerating axon. Conclusion: This novel multifunctional therapeutic strategy with a scar-homing delivery system may offer promising translational prospects for the clinical treatment of SCI.

Prevention of Diabetic Nephropathy by Modified Acidic Fibroblast Growth Factor.

BACKGROUND/AIMS: Oxidative stress (OS) contributes to all chronic diabetic complications, including diabetic nephropathy (DN). Acidic fibroblast growth factor (aFGF) has shown to confer protection from OS. However, it also has potent angiogenic activity. We hypothesized that a modified human aFGF (maFGF), with antioxidant properties but devoid of angiogenic activity, has preventative action in DN. METHODS: Streptozotocin-induced diabetic mice were treated with maFGF (intraperitoneally) daily for 1 or 6 months and were compared with untreated diabetic and non-diabetic controls. Microalbuminuria was assessed to determine functional damage. Renal cortical tissues were examined for multiple extracellular matrix proteins, vasoactive factors and OS markers. For mechanistic studies, immortalized mouse podocytes and human microvascular endothelial cells were exposed to high (25 mM) or low glucose (5 mM). OS, vasoactive factors, fibrosis and apoptosis-related gene expression were tested by real-time qPCR and Enzyme-Linked Immunosorbent Assay. Nitric oxide (NO) analyses were also performed. RESULTS: maFGF did not affect body weight and glycemia but prevented renal hypertrophy and functional changes in DN. It also prevented diabetes-induced DNA damage, nitrosative stress, vasoactive factors, angiotensinogen and endothelial NO synthase alterations. Although it failed to prevent transforming growth factor (TGF)-ß1 mRNA upregulation, it prevented fibronectin production. Similar results were obtained in vitro. Decreased NO production in vivo and in vitro was also prevented by maFGF. CONCLUSIONS: maFGF treatment prevents DN. This prevention probably involves NO production.

Combinatory repair strategy to promote axon regeneration and functional recovery after chronic spinal cord injury.

Eight weeks post contusive spinal cord injury, we built a peripheral nerve graft bridge (PNG) through the cystic cavity and treated the graft/host interface with acidic fibroblast growth factor (aFGF) and chondroitinase ABC (ChABC). This combinatorial strategy remarkably enhanced integration between host astrocytes and graft Schwann cells, allowing for robust growth, especially of catecholaminergic axons, through the graft and back into the distal spinal cord. In the absence of aFGF+ChABC fewer catecholaminergic axons entered the graft, no axons exited, and Schwann cells and astrocytes failed to integrate. In sharp contrast with the acutely bridge-repaired cord, in the chronically repaired cord only low levels of serotonergic axons regenerated into the graft, with no evidence of re-entry back into the spinal cord. The failure of axons to regenerate was strongly correlated with a dramatic increase of SOCS3 expression. While regeneration was more limited overall than at acute stages, our combinatorial strategy in the chronically injured animals prevented a decline in locomotor behavior and bladder physiology outcomes associated with an invasive repair strategy. These results indicate that PNG+aFGF+ChABC treatment of the chronically contused spinal cord can provide a permissive substrate for the regeneration of certain neuronal populations that retain a growth potential over time, and lead to functional improvements.

FGF1 - a new weapon to control type 2 diabetes mellitus.

A hypercaloric diet combined with a sedentary lifestyle is a major risk factor for the development of insulin resistance, type 2 diabetes mellitus (T2DM) and associated comorbidities. Standard treatment for T2DM begins with lifestyle modification, and includes oral medications and insulin therapy to compensate for progressive ß-cell failure. However, current pharmaceutical options for T2DM are limited in that they do not maintain stable, durable glucose control without the need for treatment intensification. Furthermore, each medication is associated with adverse effects, which range from hypoglycaemia to weight gain or bone loss. Unexpectedly, fibroblast growth factor 1 (FGF1) and its low mitogenic variants have emerged as potentially safe candidates for restoring euglycaemia, without causing overt adverse effects. In particular, a single peripheral injection of FGF1 can lower glucose to normal levels within hours, without the risk of hypoglycaemia. Similarly, a single intracerebroventricular injection of FGF1 can induce long-lasting remission of the diabetic phenotype. This Review discusses potential mechanisms by which centrally administered FGF1 improves central glucose-sensing and peripheral glucose uptake in a sustained manner. Specifically, we explore the potential crosstalk between FGF1 and glucose-sensing neuronal circuits, hypothalamic neural stem cells and synaptic plasticity. Finally, we highlight therapeutic considerations of FGF1 and compare its metabolic actions with FGF15 (rodents), FGF19 (humans) and FGF21.

Cytokine-loaded PLGA and PEG-PLGA microparticles showed similar heart regeneration in a rat myocardial infarction model.

Neuregulin (NRG1) and fibroblast growth factor (FGF1) are well known growth factors implicated in cardiomyocyte proliferation and survival, as well as in angiogenesis, the development of adult heart and the maintenance of cardiac function. NRG1 and FGF1 have become promising therapeutic agents to treat myocardial infarction (MI) disorder. Unfortunately, clinical trials performed so far reported negative efficacy results, because growth factors are rapidly degraded and eliminated from the biological tissues once administered. In order to increase their bioavailability and favour their therapeutic effects, they have been combined with poly(lactic-co-glycolic acid) and polyethylene glycol microparticles (PLGA MPs and PEG-PLGA MPs). Here we compare both types of microparticles loaded with NRG1 or FGF1 in terms of efficacy in a rat MI model. Our results showed that intramyocardial injection of NRG1 or FGF1-loaded PLGA and PEG-PLGA MPs brought about similar improvements in the ejection fraction, angiogenesis and arteriogenesis after administration into the infarcted hearts. PEG coating did not add any effect regarding MP efficacy. Both PLGA and PEG-PLGA MPs were equally phagocyted in the heart. To our knowledge, this is the first study analysing the opsonisation process in heart tissue. The results allow us to conclude that the opsonisation process is different in heart tissue compared to blood.

Catheter-based Intramyocardial Injection of FGF1 or NRG1-loaded MPs Improves Cardiac Function in a Preclinical Model of Ischemia-Reperfusion.

Cardiovascular protein therapeutics such as neuregulin (NRG1) and acidic-fibroblast growth factor (FGF1) requires new formulation strategies that allow for sustained bioavailability of the drug in the infarcted myocardium. However, there is no FDA-approved injectable protein delivery platform due to translational concerns about biomaterial administration through cardiac catheters. We therefore sought to evaluate the efficacy of percutaneous intramyocardial injection of poly(lactic-co-glycolic acid) microparticles (MPs) loaded with NRG1 and FGF1 using the NOGA MYOSTAR injection catheter in a porcine model of ischemia-reperfusion. NRG1- and FGF1-loaded MPs were prepared using a multiple emulsion solvent-evaporation technique. Infarcted pigs were treated one week after ischemia-reperfusion with MPs containing NRG1, FGF1 or non-loaded MPs delivered via clinically-translatable percutaneous transendocardial-injection. Three months post-treatment, echocardiography indicated a significant improvement in systolic and diastolic cardiac function. Moreover, improvement in bipolar voltage and decrease in transmural infarct progression was demonstrated by electromechanical NOGA-mapping. Functional benefit was associated with an increase in myocardial vascularization and remodeling. These findings in a large animal model of ischemia-reperfusion demonstrate the feasibility and efficacy of using MPs as a delivery system for growth factors and provide strong evidence to move forward with clinical studies using therapeutic proteins combined with catheter-compatible biomaterials.

Advanced Interfere Treatment of Diabetic Cardiomyopathy Rats by aFGF-Loaded Heparin-Modified Microbubbles and UTMD Technique.

This study aims to investigate the preclinical performance and mechanism of a novel strategy of aFGF-loaded heparin-modified microbubbles (aFGF-HMB) combined with ultrasound-targeted microbubble destruction (UTMD) technique for diabetic cardiomyopathy (DCM) prevention. Type 1 diabetic rats were induced by streptozotocin. Twelve weeks after intervention, indexes from transthoracic echocardiography and cardiac catheterization showed that the left ventricular function in the aFGF-HMB/UTMD group was significantly improved compared with diabetes control (DM). From Picrosirius Red staining and TUNEL staining, the aFGF-HMB/UTMD group showed significant difference from the other groups. The cardiac collagen volume fraction (CVF) and myocardial cell apoptosis index (AI) in aFGF-HMB/UTMD group decreased to 7.2 % and 7.11 % respectively, compared with the DM group (CVF = 24.5 % and AI =20.3 % respectively). The results of myocardial microvascular density (MCD) also proved the strongest inhibition of aFGF-HMB/UTMD group on DCM progress. CD31 staining of aFGF-HMB/UTMD group reached 22 n/hrp, much higher than that of DM group (9 n/hrp). These results confirmed that the abnormalities including left ventricular dysfunction, myocardial fibrosis, cardiomyocytes apoptosis and microvascular rarefaction could be suppressed by twice weekly aFGF treatments for 12 consecutive weeks (free aFGF or aFGF-HMB+/-UTMD), with the strongest improvements observed in the aFGF-HMB/UTMD group (P < 0.05 vs free aFGF or aFGF-HMB). Western blot analyses of heart tissue further revealed the highest aFGF, anti-apoptosis protein (Bcl-2), VEGF-C, pAkt, pFoxo-3a levels and strongest reduction in pro-apoptosis proteins (Bax) level in aFGF-HMB/UTMD group. Overall, aFGF-HMB combined with UTMD technique might be developed as an effective strategy to prevent DCM in future clinical therapy.

VEGFR2 inhibition by RNA interference affects cell proliferation, migration, invasion, and response to radiation in Calu-1 cells

Objective. To investigate the role of the vascular endothelial growth factor receptor 2 (VEGFR2) in the proliferation, migration, invasion, and radiation-induced apoptosis of the non-small cell lung cancer (NSCLC) cell line Calu-1. Methods. VEGFR2 gene was silenced by RNA interference in Calu-1 cells, and the expression of VEGFR2 was measured by qRT-PCR and Western blot analysis. The cells were divided into control, VEGF-treated, VEGFR2 knockdown, and VEGFR2 knockdown and VEGF-treated groups. A CCK8 assay and Transwell assay were performed to assess cell proliferation, migration, and invasion, respectively, after VEGFR2 knockdown. Western blot assays were used to detect signaling proteins downstream of VEGFR2. Cells in the groups listed above were also subjected to radiation treatment, followed by apoptosis analysis. Results. (1) RNA interference of VEGFR2 in Calu-1 cells reduced VEGFR2 mRNA (P < 0.01) and protein levels (P < 0.01). (2) VEGFR2 knockdown inhibited proliferation (P < 0.05), migration (P < 0.05), and invasion (P < 0.05) in Calu-1 cells. (3) VEGFR2 knockdown blocked the phosphorylation of protein kinase B (Akt, also known as PKB), extracellular regulated kinase (ERK) 1/2, and p38 mitogen-activated protein kinase (p38 MAPK) to various extent (P < 0.05), but did not change their total protein expression. (4) Knockdown of VEGFR2 suppressed HIF-1α protein synthesis (P < 0.05), and exacerbated apoptosis induced by radiation (P < 0.05). Conclusion. VEGFR2 gene knockdown significantly suppressed a number of cellular activities in Calu-1 cells and increased radiation-induced cell death (AU)

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