Advanced Functional Materials
Shen, H;Fan, C;You, Z;Xiao, Z;Zhao, Y;Dai, J;
| DOI: 10.1002/adfm.202110628
Spinal cord injury (SCI) often leads to the loss of motor and sensory functions and is a major challenge in neurological clinical practice. Understanding the pathophysiological changes and the inhibitory microenvironment is crucial to enable the identification of potential mechanisms for functional restoration and to provide guidance for the development of efficient treatment and repair strategies. To date, the implantation of specifically functionalized biomaterials in the lesion area has been shown to help promote axon regeneration and facilitate neuronal circuit generation by remolding SCI microenvironments. Moreover, structural and functional restoration of the spinal cord through the transplantation of naive spinal cord tissue grafts from adult donors, artificial spinal cord-like tissue developed from tissue engineering, and 3D printing will open up new avenues for SCI treatment. This review focuses on the dynamic pathophysiological changes in SCI microenvironments, biomaterials for SCI repairs, strategies for restoring spinal cord structure and function, experimental animal models, regenerative mechanisms, and clinical studies for SCI repair. The current status, recent advances, challenges, and prospects of scaffold-based SCI repair from basic to clinical settings are summarized and discussed, to provide a reference that will help to guide the future exploration and development of spinal cord regeneration strategies.
Cui, L;Guo, J;Cranfill, SL;Gautam, M;Bhattarai, J;Olson, W;Beattie, K;Challis, RC;Wu, Q;Song, X;Raabe, T;Gradinaru, V;Ma, M;Liu, Q;Luo, W;
PMID: 34986325 | DOI: 10.1016/j.neuron.2021.12.007
Whether glutamate or itch-selective neurotransmitters are used to confer itch specificity is still under debate. We focused on an itch-selective population of primary afferents expressing MRGPRA3, which highly expresses Vglut2 and the neuropeptide neuromedin B (Nmb), to investigate this question. Optogenetic stimulation of MRGPRA3+ afferents triggers scratching and other itch-related avoidance behaviors. Using a combination of optogenetics, spinal cord slice recordings, Vglut2 conditional knockout mice, and behavior assays, we showed that glutamate is essential for MRGPRA3+ afferents to transmit itch. We further demonstrated that MRGPRA3+ afferents form monosynaptic connections with both NMBR+ and NMBR- neurons and that NMB and glutamate together can enhance the activity of NMBR+ spinal DH neurons. Moreover, Nmb in MRGPRA3+ afferents and NMBR+ DH neurons are required for chloroquine-induced scratching. Together, our results establish a new model in which glutamate is an essential neurotransmitter in primary afferents for itch transmission, whereas NMB signaling enhances its activities.
Steiner, I;Flores-Tellez, T;Mevel, R;Ali, A;Wang, P;Schofield, P;Forsythe, N;Ashton, G;Taylor, C;Mills, I;Oliveira, P;McDade, S;Zeiss, D;Choudhury, A;Lacaud, G;Baena, E;
| DOI: 10.2139/ssrn.3966640
The emergence of castration resistant prostate cancer is associated with a high mortality and remains an area of unmet clinical need. We recently identified a rare subpopulation of normal prostate progenitor cells, characterized by an intrinsic resistance to androgen-deprivation and marked by the expression of LY6D. We here describe the underlying mechanisms driving castration-resistance of LY6D+ luminal progenitors and their contribution to advanced prostate cancer. We demonstrate that conditional deletion of PTEN in the murine prostate epithelium causes an expansion of transformed LY6D+ progenitor cells in proximal and distal regions of the prostate without impairing stem cell properties. Transcriptomic analyses of LY6D+ luminal cells identified an autocrine positive feed-back loop, based on the secretion of amphiregulin (AREG), further increasing cellular fitness and organoid formation. Pharmacological interference with AREG-activated MAPK-signaling overcomes the castration-resistant properties of LY6D+ cells with a near complete suppression of organoid formation. Notably, LY6D+ tumor cells are enriched in prostate specimens from high-grade and androgen-resistant prostate cancer, providing clinical evidence for their contribution to advanced and also metastatic disease. Our data indicate that the prospective identification of LY6D+ cells could allow for an early interference with MAPK-inhibitors to prevent the emergence of castration-resistant prostate cancer.
Functional coordination of non-myocytes plays a key role in adult zebrafish heart regeneration
Ma, H;Liu, Z;Yang, Y;Feng, D;Dong, Y;Garbutt, TA;Hu, Z;Wang, L;Luan, C;Cooper, CD;Li, Y;Welch, JD;Qian, L;Liu, J;
PMID: 34523214 | DOI: 10.15252/embr.202152901
Cardiac regeneration occurs primarily through proliferation of existing cardiomyocytes, but also involves complex interactions between distinct cardiac cell types including non-cardiomyocytes (non-CMs). However, the subpopulations, distinguishing molecular features, cellular functions, and intercellular interactions of non-CMs in heart regeneration remain largely unexplored. Using the LIGER algorithm, we assemble an atlas of cell states from 61,977 individual non-CM scRNA-seq profiles isolated at multiple time points during regeneration. This analysis reveals extensive non-CM cell diversity, including multiple macrophage (MC), fibroblast (FB), and endothelial cell (EC) subpopulations with unique spatiotemporal distributions, and suggests an important role for MC in inducing the activated FB and EC subpopulations. Indeed, pharmacological perturbation of MC function compromises the induction of the unique FB and EC subpopulations. Furthermore, we developed computational algorithm Topologizer to map the topological relationships and dynamic transitions between functional states. We uncover dynamic transitions between MC functional states and identify factors involved in mRNA processing and transcriptional regulation associated with the transition. Together, our single-cell transcriptomic analysis of non-CMs during cardiac regeneration provides a blueprint for interrogating the molecular and cellular basis of this process.
Photothermal mediated rolling circle amplification toward specific and direct in situ mRNA detection
Biosensors & bioelectronics
Liu, D;Li, W;Yang, M;Qiu, L;Pian, H;Huang, Y;Chen, M;Zheng, Z;
PMID: 34330037 | DOI: 10.1016/j.bios.2021.113507
Rolling circle amplification (RCA) had the prospect of assisting clinic diagnosis with advantage in in situ mRNA detection at single cell level. However, for direct mRNA detection, RCA had relatively low detection specificity and efficiency. Here, we introduced 4-(10, 15, 20-Triphenylporphyrin-5-yl)phenylamine (TPP) modified Au nanoparticle (Au-TPP) to improve the specificity of in-situ RCA. Through photothermal effect, Au-TPP acted as the specific heat source upon irradiation of 635 nm laser. The photothermal mediated RCA would be initiated only when the Au-TPP as well as the padlock anchored adjacently on the same target mRNA. Furthermore, we introduced 'C' form target-specific oligonucleotide linker probes to make generic padlock and Au-TPP for different mRNA targets, so that for a new mRNA target one does not have to redesign the padlock and the Au-TPP probe. By these strategies, we successfully developed a specific and photothermal mediated hyperbranched rolling circle amplification for direct in situ mRNA detection, suitable for both formalin-fixed paraffin-embedded (FFPE) tissue section and frozen tissue section.
Transient receptor potential canonical 5 mediates inflammatory mechanical and spontaneous pain in mice
Science translational medicine
Sadler, KE;Moehring, F;Shiers, SI;Laskowski, LJ;Mikesell, AR;Plautz, ZR;Brezinski, AN;Mecca, CM;Dussor, G;Price, TJ;McCorvy, JD;Stucky, CL;
PMID: 34039739 | DOI: 10.1126/scitranslmed.abd7702
Tactile and spontaneous pains are poorly managed symptoms of inflammatory and neuropathic injury. Here, we found that transient receptor potential canonical 5 (TRPC5) is a chief contributor to both of these sensations in multiple rodent pain models. Use of TRPC5 knockout mice and inhibitors revealed that TRPC5 selectively contributes to the mechanical hypersensitivity associated with CFA injection, skin incision, chemotherapy induced peripheral neuropathy, sickle cell disease, and migraine, all of which were characterized by elevated concentrations of lysophosphatidylcholine (LPC). Accordingly, exogenous application of LPC induced TRPC5-dependent behavioral mechanical allodynia, neuronal mechanical hypersensitivity, and spontaneous pain in naïve mice. Lastly, we found that 75% of human sensory neurons express TRPC5, the activity of which is directly modulated by LPC. On the basis of these results, TRPC5 inhibitors might effectively treat spontaneous and tactile pain in conditions characterized by elevated LPC.
Acute splanchnic vein thrombosis in patients with COVID-19: a systematic review
Digestive and Liver Disease
Buso, G;Becchetti, C;Berzigotti, A;
| DOI: 10.1016/j.dld.2021.05.021
There is increasing evidence that coronavirus disease 2019 (COVID-19) is associated with a significant risk of venous thromboembolism. While information are mainly available for deep vein thrombosis of the lower limb and pulmonary embolism, scarce data exist regarding acute splanchnic vein thrombosis (SVT) in this setting. PubMed, EMBASE and Google Scholar English-language articles published up to 30 January 2021 on SVT in COVID-19 were searched. Overall, 21 articles reporting equal number of patients were identified. 15 subjects presented with portal vein thrombosis, 11 with mesenteric vein thrombosis, four with splenic vein thrombosis, and two with Budd-Chiari syndrome. Male sex was prevalent (15 patients), and median age was 43 years (range 26–79 years). Three patients had a history of liver disease, while no subject had known myeloproliferative syndrome. Clinical presentation included mainly gastrointestinal symptoms. Anticoagulation was started in 16 patients. Three patients underwent bowel resection. Ten subjects developed gastric or bowel ischemia, seven of whom underwent bowel resection, and four died after SVT diagnosis.
Clinical and research applications of multiplexed immunohistochemistry and in situ hybridization
McGinnis, LM;Ibarra-Lopez, V;Rost, S;Ziai, J;
PMID: 33723864 | DOI: 10.1002/path.5663
Over the past decade, invention and adoption of novel multiplexing technologies for tissues have made increasing impacts in basic and translational research and, to a lesser degree, clinical medicine. Platforms capable of highly multiplexed immunohistochemistry or in situ RNA measurements promise evaluation of protein or RNA targets at levels of plex and sensitivity logs above traditional methods - all with preservation of spatial context. These methods promise objective biomarker quantification, markedly increased sensitivity, and single-cell resolution. Increasingly, development of novel technologies is enabling multi-omic interrogations with spatial correlation of RNA and protein expression profiles in the same sample. Such sophisticated methods will provide unprecedented insights into tissue biology, biomarker science and, ultimately, patient health. However, this sophistication comes at significant cost, requiring extensive time, practical knowledge, and resources to implement. This review will describe the technical features, advantages, and limitations of currently available multiplexed immunohistochemistry and spatial transcriptomic platforms. This article is protected by
Persistent repression of tau in the brain using engineered zinc finger protein transcription factors
Wegmann, S;DeVos, SL;Zeitler, B;Marlen, K;Bennett, RE;Perez-Rando, M;MacKenzie, D;Yu, Q;Commins, C;Bannon, RN;Corjuc, BT;Chase, A;Diez, L;Nguyen, HB;Hinkley, S;Zhang, L;Goodwin, A;Ledeboer, A;Lam, S;Ankoudinova, I;Tran, H;Scarlott, N;Amora, R;Surosky, R;Miller, JC;Robbins, AB;Rebar, EJ;Urnov, FD;Holmes, MC;Pooler, AM;Riley, B;Zhang, HS;Hyman, BT;
PMID: 33741591 | DOI: 10.1126/sciadv.abe1611
Neuronal tau reduction confers resilience against β-amyloid and tau-related neurotoxicity in vitro and in vivo. Here, we introduce a novel translational approach to lower expression of the tau gene MAPT at the transcriptional level using gene-silencing zinc finger protein transcription factors (ZFP-TFs). Following a single administration of adeno-associated virus (AAV), either locally into the hippocampus or intravenously to enable whole-brain transduction, we selectively reduced tau messenger RNA and protein by 50 to 80% out to 11 months, the longest time point studied. Sustained tau lowering was achieved without detectable off-target effects, overt histopathological changes, or molecular alterations. Tau reduction with AAV ZFP-TFs was able to rescue neuronal damage around amyloid plaques in a mouse model of Alzheimer's disease (APP/PS1 line). The highly specific, durable, and controlled knockdown of endogenous tau makes AAV-delivered ZFP-TFs a promising approach for the treatment of tau-related human brain diseases.
SARS-CoV-2 infection aggravates chronic comorbidities of cardiovascular diseases and diabetes in mice
Animal models and experimental medicine
Ma, Y;Lu, D;Bao, L;Qu, Y;Liu, J;Qi, X;Yu, L;Zhang, X;Qi, F;Lv, Q;Liu, Y;Shi, X;Sun, C;Li, J;Wang, J;Han, Y;Gao, K;Dong, W;Liu, N;Gao, S;Xue, J;Wei, Q;Pan, S;Gao, H;Zhang, L;Qin, C;
PMID: 33738432 | DOI: 10.1002/ame2.12155
Cardiovascular diseases (CVDs) and diabetes mellitus (DM) are top two chronic comorbidities that increase the severity and mortality of COVID-19. However, how SARS-CoV-2 alters the progression of chronic diseases remain unclear. We used adenovirus to deliver h-ACE2 to lung to enable SARS-CoV-2 infection in mice. SARS-CoV-2's impacts on pathogenesis of chronic diseases were studied through histopathological, virologic and molecular biology analysis. Pre-existing CVDs resulted in viral invasion, ROS elevation and activation of apoptosis pathways contribute myocardial injury during SARS-CoV-2 infection. Viral infection increased fasting blood glucose and reduced insulin response in DM model. Bone mineral density decreased shortly after infection, which associated with impaired PI3K/AKT/mTOR signaling. We established mouse models mimicked the complex pathological symptoms of COVID-19 patients with chronic diseases. Pre-existing diseases could impair the inflammatory responses to SARS-CoV-2 infection, which further aggravated the pre-existing diseases. This work provided valuable information to better understand the interplay between the primary diseases and SARS-CoV-2 infection.
Distinct subtypes of proprioceptive dorsal root ganglion neurons regulate adaptive proprioception in mice
Wu, H;Petitpré, C;Fontanet, P;Sharma, A;Bellardita, C;Quadros, RM;Jannig, PR;Wang, Y;Heimel, JA;Cheung, KKY;Wanderoy, S;Xuan, Y;Meletis, K;Ruas, J;Gurumurthy, CB;Kiehn, O;Hadjab, S;Lallemend, F;
PMID: 33589589 | DOI: 10.1038/s41467-021-21173-9
Proprioceptive neurons (PNs) are essential for the proper execution of all our movements by providing muscle sensory feedback to the central motor network. Here, using deep single cell RNAseq of adult PNs coupled with virus and genetic tracings, we molecularly identify three main types of PNs (Ia, Ib and II) and find that they segregate into eight distinct subgroups. Our data unveil a highly sophisticated organization of PNs into discrete sensory input channels with distinct spatial distribution, innervation patterns and molecular profiles. Altogether, these features contribute to finely regulate proprioception during complex motor behavior. Moreover, while Ib- and II-PN subtypes are specified around birth, Ia-PN subtypes diversify later in life along with increased motor activity. We also show Ia-PNs plasticity following exercise training, suggesting Ia-PNs are important players in adaptive proprioceptive function in adult mice.
Epithelial expression of Gata4 and Sox2 regulates specification of the squamous-columnar junction via MAPK/ERK signaling in mice
Sankoda, N;Tanabe, W;Tanaka, A;Shibata, H;Woltjen, K;Chiba, T;Haga, H;Sakai, Y;Mandai, M;Yamamoto, T;Yamada, Y;Uemoto, S;Kawaguchi, Y;
PMID: 33495473 | DOI: 10.1038/s41467-021-20906-0
The squamous-columnar junction (SCJ) is a boundary consisting of precisely positioned transitional epithelium between the squamous and columnar epithelium. Transitional epithelium is a hotspot for precancerous lesions, and is therefore clinically important; however, the origins and physiological properties of transitional epithelium have not been fully elucidated. Here, by using mouse genetics, lineage tracing, and organoid culture, we examine the development of the SCJ in the mouse stomach, and thus define the unique features of transitional epithelium. We find that two transcription factors, encoded by Sox2 and Gata4, specify primitive transitional epithelium into squamous and columnar epithelium. The proximal-distal segregation of Sox2 and Gata4 expression establishes the boundary of the unspecified transitional epithelium between committed squamous and columnar epithelium. Mechanistically, Gata4-mediated expression of the morphogen Fgf10 in the distal stomach and Sox2-mediated Fgfr2 expression in the proximal stomach induce the intermediate regional activation of MAPK/ERK, which prevents the differentiation of transitional epithelial cells within the SCJ boundary. Our results have implications for tissue regeneration and tumorigenesis, which are related to the SCJ.