TANGO1 inhibitors reduce collagen secretion and limit tissue scarring.

Uncontrolled secretion of ECM proteins, such as collagen, can lead to excessive scarring and fibrosis and compromise tissue function. Despite the widespread occurrence of fibrotic diseases and scarring, effective therapies are lacking. A promising approach would be to limit the amount of collagen released from hyperactive fibroblasts. We have designed membrane permeant peptide inhibitors that specifically target the primary interface between TANGO1 and cTAGE5, an interaction that is required for collagen export from endoplasmic reticulum exit sites (ERES). Application of the peptide inhibitors leads to reduced TANGO1 and cTAGE5 protein levels and a corresponding inhibition in the secretion of several ECM components, including collagens. Peptide inhibitor treatment in zebrafish results in altered tissue architecture and reduced granulation tissue formation during cutaneous wound healing. The inhibitors reduce secretion of several ECM proteins, including collagens, fibrillin and fibronectin in human dermal fibroblasts and in cells obtained from patients with a generalized fibrotic disease (scleroderma). Taken together, targeted interference of the TANGO1-cTAGE5 binding interface could enable therapeutic modulation of ERES function in ECM hypersecretion, during wound healing and fibrotic processes.

Hydrogels to Recapture Extracellular Matrix Cues That Regulate Vascularization.

The ECM (extracellular matrix) is a 3-dimensional network that supports cellular responses and maintains structural tissue integrity in healthy and pathological conditions. The interactions between ECM and cells trigger signaling cascades that lead to phenotypic changes and structural and compositional turnover of the ECM, which in turn regulates vascular cell behavior. Hydrogel biomaterials are a powerful platform for basic and translational studies and clinical applications due to their high swelling capacity and exceptional versatility in compositions and properties. This review highlights recent developments and uses of engineered natural hydrogel platforms that mimic the ECM and present defined biochemical and mechanical cues for vascularization. Specifically, we focus on modulating vascular cell stimulation and cell-ECM/cell-cell interactions in the microvasculature that are the established biomimetic microenvironment.

Psychedelics reopen the social reward learning critical period.

Psychedelics are a broad class of drugs defined by their ability to induce an altered state of consciousness1,2. These drugs have been used for millennia in both spiritual and medicinal contexts, and a number of recent clinical successes have spurred a renewed interest in developing psychedelic therapies3-9. Nevertheless, a unifying mechanism that can account for these shared phenomenological and therapeutic properties remains unknown. Here we demonstrate in mice that the ability to reopen the social reward learning critical period is a shared property across psychedelic drugs. Notably, the time course of critical period reopening is proportional to the duration of acute subjective effects reported in humans. Furthermore, the ability to reinstate social reward learning in adulthood is paralleled by metaplastic restoration of oxytocin-mediated long-term depression in the nucleus accumbens. Finally, identification of differentially expressed genes in the 'open state' versus the 'closed state' provides evidence that reorganization of the extracellular matrix is a common downstream mechanism underlying psychedelic drug-mediated critical period reopening. Together these results have important implications for the implementation of psychedelics in clinical practice, as well as the design of novel compounds for the treatment of neuropsychiatric disease.

Introducing aesthetic regenerative scaffolds: An immunological perspective.

BACKGROUND: Skin aging arises from immunological responses to tissue deterioration and damage. Tissue repair processes encompass the regeneration of original tissue and 'scarless' wound healing seen in foetuses, and the extreme fibrotic responses and scarring seen in adults. Anti-aging aesthetic medicine uses interventions like biomaterial-based fillers to influence these immunological responses and renew aged tissue structure and function. At filler injection sites, an inflammatory response occurs that causes a spectrum of outcomes, ranging from tissue regeneration to fibrosis and filler encapsulation. Importantly, the resulting inflammatory pathway can be predetermined by the biomaterial injected. AIMS: By understanding this immunological process, we can develop Aesthetic Regenerative Scaffolds (ARS) - aesthetic injectable biomaterials - to direct inflammatory wound healing away from chronic, fibrotic responses, and towards physiological tissue regeneration. MATERIALS AND METHODS: We identified and reviewed literature on the immunological and cellular responses to injected dermal fillers, whereby the wound healing response to the injection was moderated under the influence of an injected biomaterial. RESULTS: We described the mechanisms of dermal wound healing and the use of ARS to direct healing towards tissue regeneration instead of scarring. We also summarised studies on extracellular matrix remodeling by calcium hydroxylapatite. We found that Calcium hydroxylapatite fillers produce collagen as they gradually degrade and their spherical structures serve as a scaffold for tissue regeneration. Furthermore, CaHA improved fibroblast contractility, collagen type III and elastin production, proliferation and angiogenesis with less inflammation than hyaluronic acid fillers. DISCUSSION: Regneration pathways can be influenced at specific points between a facial filler biomaterial and the wound healingmechanisms at its site of implantaion. CONCLUSION: Physicians can select scaffolds that direct the immune response away from a fibrotic chronic inflammatory pathway and towards regeneration to enable true repair of the aging skin.

Gardenoside ameliorates inflammation and inhibits ECM degradation in IL-1ß-treated rat chondrocytes via suppressing NF-κB signaling pathways.

Osteoarthritis (OA) places a significant burden on society and finance, and there is presently no effective treatment beside late replacement surgery and symptomatic relief. The therapy of OA requires additional research. Gardenoside is a naturally compound extracted from Gardenia jasminoides Ellis, which has a variety of anti-inflammatory effects. However, few studies have been conducted to determine the role of gardenoside in OA. This study aimed to explore whether gardenoside has effect in OA treatment. Rat primary chondrocytes were treated with IL-1ß to simulate inflammatory environmental conditions and OA in vitro. We examined the effects of gardenoside at concentrations ranging from 0 to 200 µM on the viability of rat chondrocytes and selected 10 µM for further study. Via in vitro experiments, our study found that gardenoside lowers the gene expression of COX-2, iNOS, IL-6, and reduced the ROS production of chondrocytes induced by IL-1ß. Moreover, it effectively alleviates ECM degradation caused by IL-1ß and promotes the ECM synthesis in chondrocytes by upregulating collagen-II and the ACAN expression, downregulating the expression of MMP-3, MMP-13, and ADAMTS-5 expression. Further, our study showed that gardenoside inhibits NF-κB signaling pathway activated by IL-1ß in chondrocytes. We established an OA rat model by anterior cruciate ligament transection (ACLT). The animals were then periodically injected with gardenoside into the knee articular cavity. In vivo study suggested that gardenoside attenuates OA progression in rats. As a whole, in vitro and in vivo results highlight gardenoside is a promising OA treatment agent.

[Research advances on application of botulinum toxin type A in scar prevention and treatment].

The wound healing time, tension of wound edge, proliferation of fibroblast, and extracellular matrix deposition are the important factors of scar formation, and botulinum toxin type A can regulate the above. Prevention and treatment of scar with botulinum toxin type A is one of the hot topics of clinical research in recent years. This paper briefly reviews researches by scholars at home and abroad on the mechanism, clinical application, complications, and adverse effects of botulinum toxin type A in scar prevention and treatment.

Epigallocatechin-3-O-gallate promotes extracellular matrix and inhibits inflammation in IL-1ß stimulated chondrocytes by the PTEN/miRNA-29b pathway.

CONTEXT: Epigallocatechin-3-O-gallate (EGCG) exhibits anti-arthritic activity. MiR-29b-3p provokes chondrocyte apoptosis and promotes the initiation and development of osteoarthritis (OA). OBJECTIVE: To explore the roles of EGCG and miR-29b-3p in interleukin-1ß (IL-1ß)-stimulated chondrocytes. MATERIALS AND METHODS: HE and Safranin O staining were used to detect the pathological changes of cartilage tissue in OA patients and healthy people. OA-like chondrocyte injury was mimicked by 5 ng/mL IL-1ß stimulation for 24 h in vitro, and after transfection with miR-29b-3p mimics and pcDNA-PTEN, IL-1ß-stimulated chondrocytes were pre-treated with EGCG (20 and 50 µM) for 2 h. Cell viability, colony numbers, apoptosis rate, the levels of IL-6 and matrix metalloproteinase-13 (MMP-13), miR-19b-3p, PTEN and apoptosis-associated proteins in chondrocytes were evaluated. RESULTS: MiR-29b-3p level was upregulated in cartilage tissues of OA patients (3.5-fold change, p < 0.001) and IL-1ß stimulated chondrocytes (two fold change, p < 0.001). The matrix staining was weakened and unevenly distributed, and the chondrocytes were arranged disorderly in the tissues of patients with OA. EGCG (20 and 50 µM) increases viability and decreases the levels of miR-29b-3p and MMP-13 and IL-6 in IL-1ß stimulated chondrocytes (p < 0.05). MiR-29b-3p mimics reversed the effects above 50 µM EGCG (p < 0.05). Furthermore, PTEN overexpression abrogated the effects of miR-29b-3p mimics on viability, colony numbers, apoptosis rate and the levels of Bcl-2, MMP-13, IL-6, Bax and cleaved caspase 3 in IL-1ß-stimulated chondrocytes (p < 0.01). DISCUSSION AND CONCLUSIONS: EGCG is a potential candidate for the treatment of OA, which also can be explored in a novel therapeutic method for other degenerative or inflammatory disorders.

Ultraviolet radiation-induced degradation of dermal extracellular matrix and protection by green tea catechins: a randomized controlled trial.

BACKGROUND: Loss and remodelling of the dermal extracellular matrix (ECM) are key features of photodamaged human skin. Green tea catechins (GTCs) have been explored for their anti-inflammatory and chemopreventive properties, but data on the impact of GTCs on ultraviolet radiation (UVR)-induced changes to the dermal ECM are lacking. AIM: To investigate the effect of an inflammatory dose of solar-simulated UVR on human dermal ECM and potential for protection by GTCs in a double-blind randomized controlled trial. METHODS: In total, 50 healthy white (Fitzpatrick skin type I-II) adults aged 18-65 years were randomized to a combination of GTCs 540 mg plus vitamin C 50 mg or to placebo twice daily for 12 weeks. The impact of solar-simulated UVR at 3 × minimal erythema dose on the dermal collagen and elastic fibre networks was assessed by histology and immunohistochemistry in all participants at baseline. The impact of GTC supplementation on UVR-induced effects was compared between the groups post-supplementation. RESULTS: The area of papillary dermis covered by collagen and elastic fibres was significantly lower (P < 0.001) in UVR-exposed skin than in unexposed skin. Significantly lower levels of fibrillin-rich microfibrils (P = 0.02), fibulin-2 (P < 0.001) and fibulin-5 (P < 0.001) were seen in UVR-exposed than unexposed skin, while procollagen-1 deposition was significantly higher in UVR-exposed skin (P = 0.01). Following GTC supplementation, the UVR-induced change in fibulin-5 was abrogated in the active group but not the placebo group, with no difference between the two groups for other components. CONCLUSIONS: Acute UVR induced significant changes in the human dermal collagen and elastic fibre networks, whereas oral GTCs conferred specific UVR protection to fibulin-5. Future studies could explore the impact of GTCs on the effects of repeated suberythemal UVR exposure of human skin.

Mitochondrial fission links ECM mechanotransduction to metabolic redox homeostasis and metastatic chemotherapy resistance.

Metastatic breast cancer cells disseminate to organs with a soft microenvironment. Whether and how the mechanical properties of the local tissue influence their response to treatment remains unclear. Here we found that a soft extracellular matrix empowers redox homeostasis. Cells cultured on a soft extracellular matrix display increased peri-mitochondrial F-actin, promoted by Spire1C and Arp2/3 nucleation factors, and increased DRP1- and MIEF1/2-dependent mitochondrial fission. Changes in mitochondrial dynamics lead to increased production of mitochondrial reactive oxygen species and activate the NRF2 antioxidant transcriptional response, including increased cystine uptake and glutathione metabolism. This retrograde response endows cells with resistance to oxidative stress and reactive oxygen species-dependent chemotherapy drugs. This is relevant in a mouse model of metastatic breast cancer cells dormant in the lung soft tissue, where inhibition of DRP1 and NRF2 restored cisplatin sensitivity and prevented disseminated cancer-cell awakening. We propose that targeting this mitochondrial dynamics- and redox-based mechanotransduction pathway could open avenues to prevent metastatic relapse.

Network modeling predicts personalized gene expression and drug responses in valve myofibroblasts cultured with patient sera.

Aortic valve stenosis (AVS) patients experience pathogenic valve leaflet stiffening due to excessive extracellular matrix (ECM) remodeling. Numerous microenvironmental cues influence pathogenic expression of ECM remodeling genes in tissue-resident valvular myofibroblasts, and the regulation of complex myofibroblast signaling networks depends on patient-specific extracellular factors. Here, we combined a manually curated myofibroblast signaling network with a data-driven transcription factor network to predict patient-specific myofibroblast gene expression signatures and drug responses. Using transcriptomic data from myofibroblasts cultured with AVS patient sera, we produced a large-scale, logic-gated differential equation model in which 11 biochemical and biomechanical signals were transduced via a network of 334 signaling and transcription reactions to accurately predict the expression of 27 fibrosis-related genes. Correlations were found between personalized model-predicted gene expression and AVS patient echocardiography data, suggesting links between fibrosis-related signaling and patient-specific AVS severity. Further, global network perturbation analyses revealed signaling molecules with the most influence over network-wide activity, including endothelin 1 (ET1), interleukin 6 (IL6), and transforming growth factor ß (TGFß), along with downstream mediators c-Jun N-terminal kinase (JNK), signal transducer and activator of transcription (STAT), and reactive oxygen species (ROS). Lastly, we performed virtual drug screening to identify patient-specific drug responses, which were experimentally validated via fibrotic gene expression measurements in valvular interstitial cells cultured with AVS patient sera and treated with or without bosentan-a clinically approved ET1 receptor inhibitor. In sum, our work advances the ability of computational approaches to provide a mechanistic basis for clinical decisions including patient stratification and personalized drug screening.

Impact of Collagen Crosslinking on Dislocated Human Shoulder Capsules-Effect on Structural and Mechanical Properties.

Classical treatments of shoulder instability are associated with recurrence. To determine whether the modification of the capsule properties may be an alternative procedure, the effect of crosslinking treatment on the structure and mechanical properties of diseased human shoulder capsules was investigated. Joint capsules harvested from patients during shoulder surgery (n = 5) were treated or not with UV and/or riboflavin (0.1%, 1.0% and 2.5%). The structure and the mechanical properties of the capsules were determined by atomic force microscopy. The effect of treatments on cell death was investigated. Collagen fibrils were well-aligned and adjacent to each other with a D-periodicity of 66.9 ± 3.2 nm and a diameter of 71.8 ± 15.4 nm in control untreated capsules. No effect of treatments was observed on the organization of the collagen fibrils nor on their intrinsic characteristics, including D-periodicity or their mean diameter. The treatments also did not induce cell death. In contrast, UV + 2.5% riboflavin induced capsule stiffness, as revealed by the increased Young's modulus values (p < 0.0001 for each patient). Our results showed that the crosslinking procedure changed the biomechanics of diseased capsules, while keeping their structural organisation unchanged at the single fibril level. The UV/riboflavin crosslinking procedure may be a promising way to preserve the functions of collagen-based tissues and tune their elasticity for clinically relevant treatments.

Tetrandrine reduces oxidative stress, apoptosis, and extracellular matrix degradation and improves intervertebral disc degeneration by inducing autophagy.

Tetrandrine (TET) was reported to be an autophagy agonist, and the activating autophagy could delay intervertebral disc degeneration (IDD). Our study focused on exploring whether TET attenuated tert butyl hydrogen peroxide (TBHP)-induced nucleus pulposus (NP) cell injury and delayed rat IDD by inducing autophagy. In vitro, cytotoxicity was detected by MTT assay, ROS was measured with DCFH-DA probe, MDA, and SOD content was evaluated through ELISA, NP cell apoptosis was tested by flow cytometry, protein expression was detected by Western blot, in particular, LC3 expression was assessed by immunofluorescence. In vivo, pathological changes were estimated by HE and safranin-O staining, related protein expression was measured by immunohistochemistry, and the apoptosis was detected by TUNEL. Compared with the control group, oxidative stress, apoptosis, and extracellular matrix (ECM) degradation were increased, the expression of cleaved caspase-3,9, aggrecan and collagen II were reduced, and the expression of MMP13 and ADAMTS5 were up-regulated in TBHP-treated NP cells. Moreover, TET could reverse the effect of TBHP on NP cells. Further, TET enhanced autophagy in NP cells by amplifying the LC3 II/LC3 I/ratio and reducing p62 expression, which attenuated oxidative stress, apoptosis, and ECM degradation in TBHP-treated NP cells. In addition, in vivo, TET delayed rat IDD, increased the expression of LC3 and collagen II, and weakened apoptosis. TET inhibited oxidative stress, apoptosis, and ECM degradation in TBHP-treated NP cells by inducing autophagy, and alleviated IDD. These indicated that TET might be a potential candidate drug for the treatment of IDD.

LDHA mediated degradation of extracellular matrix is a potential target for the treatment of aortic dissection.

Aortic dissection (AD) is a disease with high mortality and lacks effective drug treatment. Recent studies have shown that the development of AD is closely related to glucose metabolism. Lactate dehydrogenase A (LDHA) is a key glycolytic enzyme and plays an important role in cardiovascular disease. However, the role of LDHA in the progression of AD remains to be elucidated. Here, we found that the level of LDHA was significantly elevated in AD patients and the mouse model established by BAPN combined with Ang II. In vitro, the knockdown of LDHA reduced the growth of human aortic vascular smooth muscle cells (HAVSMCs), glucose consumption, and lactate production induced by PDGF-BB. The overexpression of LDHA in HAVSMCs promoted the transformation of HAVSMCs from contractile phenotype to synthetic phenotype, and increased the expression of MMP2/9. Mechanistically, LDHA promoted MMP2/9 expression through the LDHA-NDRG3-ERK1/2-MMP2/9 pathway. In vivo, Oxamate, LDH and lactate inhibitor, reduced the degradation of elastic fibers and collagen deposition, inhibited the phenotypic transformation of HAVSMCs from contractile phenotype to synthetic phenotype, reduced the expression of NDRG3, p-ERK1/2, and MMP2/9, and delayed the progression of AD. To sum up, the increase of LDHA promotes the production of MMP2/9, stimulates the degradation of extracellular matrix (ECM), and promoted the transformation of HAVSMCs from contractile phenotype to synthetic phenotype. Oxamate reduced the progression of AD in mice. LDHA may be a therapeutic target for AD.

Oral treatment of 4-methylumbelliferone reduced perineuronal nets and improved recognition memory in mice.

Hyaluronan (HA) is a core constituent of perineuronal nets (PNNs) that surround subpopulations of neurones. The PNNs control synaptic stabilization in both the developing and adult central nervous system, and disruption of PNNs has shown to reactivate neuroplasticity. We investigated the possibility of memory prolongation by attenuating PNN formation using 4-methylumbelliferone (4-MU), an inhibitor of HA synthesis. Adult C57BL/6 mice were fed with chow containing 5% (w/w) 4-MU for 6 months, at a dose ~6.7 mg/g/day. The oral administration of 4-MU reduced the glycosaminoglycan level in the brain to 72% and the spinal cord to 50% when compared to the controls. Spontaneous object recognition test (SOR) performed at 2, 3, 6 and 7 months showed a significant increase in SOR score in the 6-months treatment group 24 h after object presentation. The effect however did not persist in the washout group (1-month post treatment). Immunohistochemistry confirmed a reduction of PNNs, with shorter and less arborization of aggrecan staining around dendrites in hippocampus after 6 months of 4-MU treatment. Histopathological examination revealed mild atrophy in articular cartilage but it did not affect the motor performance as demonstrated in rotarod test. In conclusion, systemic oral administration of 4-MU for 6 months reduced PNN formation around neurons and enhanced memory retention in mice. However, the memory enhancement was not sustained despite the reduction of PNNs, possibly due to the lack of memory enhancement training during the washout period. Our results suggest that 4-MU treatment might offer a strategy for PNN modulation in memory enhancement.

Comparison of chemical profiles, antioxidation, inhibition of skin extracellular matrix degradation, and anti-tyrosinase activity between mycelium and fruiting body of Cordyceps militaris and Isaria tenuipes.

CONTEXT: Cordyceps militaris and Isaria tenuipes (Cordycipitaceae) are high-value fungi that are used for health-promoting food supplements. Since laboratory cultivation has begun for these fungi, increased output has been achieved. OBJECTIVE: This study compared the chemical profiles, antioxidant, anti-tyrosinase, and skin extracellular matrix degradation inhibition between mycelium and fruiting body of C. militaris and I. tenuipes. MATERIALS AND METHODS: The antioxidative potential of 10% v/v aqueous infused extract from each fungus was separately investigated using 2,2-azinobis(3-ethylbenzo-thiazoline-6-sulphonic acid) (ABTS), 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing antioxidant ability, and ferric thiocyanate methods. The inhibition against MMP-1, elastase, and hyaluronidase were determined to reveal their anti-wrinkle potential. Anti-tyrosinase activities were determined. RESULTS: C. militaris and I. tenuipes extracts were found to contain a wide range of bioactive compounds, including phenolics, flavonoids, and adenosine. A correlation was discovered between the chemical compositions and their biological activities. The extract from I. tenuipes fruiting body (IF) was highlighted as an extraordinary elastase inhibitor (IC50 = 0.006 ± 0.004 mg/mL), hyaluronidase inhibitor (IC50: 30.3 ± 3.2 mg/mL), and antioxidant via radical scavenging (ABTS IC50: 0.22 ± 0.02 mg/mL; DPPH IC50: 0.05 ± 0.02 mg/mL), thereby reducing ability (EC1: 95.3 ± 4.8 mM FeSO4/g extract) and lipid peroxidation prevention (IC50: 0.40 ± 0.11 mg/mL). IF had a three-times higher EC1 value than ascorbic acid and significantly higher elastase inhibition than epigallocatechin gallate. DISCUSSION AND CONCLUSIONS: IF is proposed as a powerful natural extract with antioxidant and anti-wrinkle properties; therefore, it is suggested for further use in pharmaceutical, cosmeceutical, and nutraceutical industries.

Immunomodulatory Properties and Osteogenic Activity of Polyetheretherketone Coated with Titanate Nanonetwork Structures.

Polyetheretherketone (PEEK) is a potential substitute for conventional metallic biomedical implants owing to its superior mechanical and chemical properties, as well as biocompatibility. However, its inherent bio-inertness and poor osseointegration limit its use in clinical applications. Herein, thin titanium films were deposited on the PEEK substrate by plasma sputtering, and porous nanonetwork structures were incorporated on the PEEK surface by alkali treatment (PEEK-TNS). Changes in the physical and chemical characteristics of the PEEK surface were analyzed to establish the interactions with cell behaviors. The osteoimmunomodulatory properties were evaluated using macrophage cells and osteoblast lineage cells. The functionalized nanostructured surface of PEEK-TNS effectively promoted initial cell adhesion and proliferation, suppressed inflammatory responses, and induced macrophages to anti-inflammatory M2 polarization. Compared with PEEK, PEEK-TNS provided a more beneficial osteoimmune environment, including increased levels of osteogenic, angiogenic, and fibrogenic gene expression, and balanced osteoclast activities. Furthermore, the crosstalk between macrophages and osteoblast cells showed that PEEK-TNS could provide favorable osteoimmunodulatory environment for bone regeneration. PEEK-TNS exhibited high osteogenic activity, as indicated by alkaline phosphatase activity, osteogenic factor production, and the osteogenesis/osteoclastogenesis-related gene expression of osteoblasts. The study establishes that the fabrication of titanate nanonetwork structures on PEEK surfaces could extract an adequate immune response and favorable osteogenesis for functional bone regeneration. Furthermore, it indicates the potential of PEEK-TNS in implant applications.

Short-term tetrabromobisphenol A exposure promotes fibrosis of human uterine fibroid cells in a 3D culture system through TGF-beta signaling.

Tetrabromobisphenol A (TBBPA), a derivative of BPA, is a ubiquitous environmental contaminant with weak estrogenic properties. In women, uterine fibroids are highly prevalent estrogen-responsive tumors often with excessive accumulation of extracellular matrix (ECM) and may be the target of environmental estrogens. We have found that BPA has profibrotic effects in vitro, in addition to previous reports of the in vivo fibrotic effects of BPA in mouse uterus. However, the role of TBBPA in fibrosis is unclear. To investigate the effects of TBBPA on uterine fibrosis, we developed a 3D human uterine leiomyoma (ht-UtLM) spheroid culture model. Cell proliferation was evaluated in 3D ht-UtLM spheroids following TBBPA (10-6 -200 µM) administration at 48 h. Fibrosis was assessed using a Masson's Trichrome stain and light microscopy at 7 days of TBBPA (10-3  µM) treatment. Differential expression of ECM and fibrosis genes were determined using RT² Profiler™ PCR arrays. Network and pathway analyses were conducted using Ingenuity Pathway Analysis. The activation of pathway proteins was analyzed by a transforming growth factor-beta (TGFB) protein array. We found that TBBPA increased cell proliferation and promoted fibrosis in 3D ht-UtLM spheroids with increased deposition of collagens. TBBPA upregulated the expression of profibrotic genes and corresponding proteins associated with the TGFB pathway. TBBPA activated TGFB signaling through phosphorylation of TGFBR1 and downstream effectors-small mothers against decapentaplegic -2 and -3 proteins (SMAD2 and SMAD3). The 3D ht-UtLM spheroid model is an effective system for studying environmental agents on human uterine fibrosis. TBBPA can promote fibrosis in uterine fibroid through TGFB/SMAD signaling.

Lysophosphatidylcholine disrupts cell adhesion and induces anoikis in hepatocytes.

Lysophosphatidylcholine (LPC), the active metabolite of palmitate, triggers hepatocyte death by activating endoplasmic reticulum stress and JNK signalling-mediated lipoapoptosis. However, LPC-induced cytotoxicity in hepatocytes is not well understood. Here, we found for the first time that LPC-induced cell rounding occurred prior to apoptosis. LPC-induced rounding of cells reduced both cell-extracellular matrix (ECM) adhesion and cell-cell junctions, which promoted detachment-induced apoptosis (defined as anoikis) in hepatocytes. Further study revealed that LPC altered cellular morphology and cell adhesion by inhibiting integrin and cadherin signalling-mediated microfilament polymerization. We also found that ECM supplementation and microfilament cytoskeletal stabilization inhibited LPC-induced hepatocyte death by attenuating anoikis. Our data indicate a novel cytotoxic process and signalling pathway induced by LPC.

Challenges in the Development of Biological Approaches for the Treatment of Degenerative Disc Disease.

There are numerous innovative and promising approaches aimed at slowing, reversing, or healing degenerative disc disease. However, multiple treatment-specific impediments slow progress toward realizing the benefits of these therapies. First, the exact pathophysiology underlying degenerative disc disease remains complicated and challenging to study. In addition, the study of the spine and intervertebral disc in animal models is difficult to translate to humans, hindering the utility of preclinical research. Biological treatments are subject to the complex biomechanical environment in which native discs degenerate. The regulatory approval environment for these therapeutics will likely involve a high degree of scrutiny. Finally, patient selection and assessment of outcomes are a particular challenge in this clinical setting.

Substrate stiffness regulates the differentiation profile and functions of osteoclasts via cytoskeletal arrangement.

OBJECTIVES: Aging and common diseases alter the stiffness of bone tissue, causing changes to the microenvironment of the mechanosensitive bone cells. Osteoclasts, the sole bone-resorbing cells, play a vital role in bone remodeling. This study was performed to elucidate the mechanism through which osteoclasts sense and react to substrate stiffness signals. MATERIALS AND METHODS: We fabricated polydimethylsiloxane (PDMS) substrates of different stiffness degrees for osteoclast formation progressed from osteoclast precursors including bone marrow-derived macrophages (BMMs) and RAW264.7 monocytes. Osteoclast differentiation in response to the stiffness signals was determined by examining the cell morphology, fusion/fission activities, transcriptional profile, and resorption function. Cytoskeletal changes and mechanosensitive adhesion molecules were also assessed. RESULTS: Stiffer PDMS substrates accelerated osteoclast differentiation, firstly observed by variations in their morphology and fusion/fission activities. Upregulation of canonical osteoclast markers (Nfatc1, Acp5, Ctsk, Camk2a, Mmp9, Rela, and Traf6) and the fusion master regulator DC-stamp were detected on stiffer substrates, with similar increases in their bone resorption functions. Additionally, the activation of cytoskeleton-associated adhesion molecules, including fibronectin and integrin αvß3, followed by biochemical signaling cascades of paxillin, FAK, PKC, and RhoA, was detected on the stiffer substrates. CONCLUSIONS: This is the first study to provide evidence proving that extracellular substrate stiffness is a strong determinant of osteoclast differentiation and functions. Higher stiffness upregulated the differentiation profile and activity of osteoclasts, revealing the mechanical regulation of osteoclast activity in bone homeostasis and diseases.