Dermal TRPV1 innervations engage a macrophage- and fibroblast-containing pathway to activate hair growth in mice.

Pain, detected by nociceptors, is an integral part of injury, yet whether and how it can impact tissue physiology and recovery remain understudied. Here, we applied chemogenetics in mice to locally activate dermal TRPV1 innervations in naive skin and found that it triggered new regenerative cycling by dormant hair follicles (HFs). This was preceded by rapid apoptosis of dermal macrophages, mediated by the neuropeptide calcitonin gene-related peptide (CGRP). TRPV1 activation also triggered a macrophage-dependent induction of osteopontin (Spp1)-expressing dermal fibroblasts. The neuropeptide CGRP and the extracellular matrix protein Spp1 were required for the nociceptor-triggered hair growth. Finally, we showed that epidermal abrasion injury induced Spp1-expressing dermal fibroblasts and hair growth via a TRPV1 neuron and CGRP-dependent mechanism. Collectively, these data demonstrated a role for TRPV1 nociceptors in orchestrating a macrophage and fibroblast-supported mechanism to promote hair growth and enabling the efficient restoration of this mechano- and thermo-protective barrier after wounding.

A study on the role of serum uric acid in differentiating acute inflammatory demyelinating polyneuropathy from acute-onset chronic inflammatory demyelinating polyneuropathy.

BACKGROUND AND PURPOSE: Clinical symptoms and laboratory indices for acute inflammatory demyelinating polyneuropathy (AIDP), a variant of Guillain-Barré syndrome, and acute-onset chronic inflammatory demyelinating polyneuropathy (A-CIDP) were analyzed to identify factors that could contribute to early differential diagnosis. METHODS: A retrospective chart review was performed on 44 AIDP and 44 A-CIDP patients looking for any demographic characteristics, clinical manifestations or laboratory parameters that might differentiate AIDP from acutely presenting CIDP. RESULTS: In Guillain-Barré syndrome patients (N = 63), 69.84% (N = 44) were classified as having AIDP, 19.05% (N = 12) were found to have acute motor axonal neuropathy, 6.35% (N = 4) were found to have acute motor and sensory axonal neuropathy, and 4.76% (N = 3) were found to have Miller Fisher syndrome. Serum uric acid (UA) was higher in A-CIDP patients (329.55 ± 72.23 µmol/L) than in AIDP patients (221.08 ± 71.32 µmol/L) (p = 0.000). Receiver operating characteristic analyses indicated that the optimal UA cutoff was 283.50 µmol/L. Above this level, patients were more likely to present A-CIDP than AIDP (specificity 81.80%, sensitivity 81.80%). During the follow-up process, serum samples were effectively collected from 19 AIDP patients during the rehabilitation phase and 28 A-CIDP patients during the remission stage, and it was found that UA levels were significantly increased in A-CIDP (remission) (298.9 ± 90.39 µmol/L) compared with AIDP (rehabilitation) (220.1 ± 108.2 µmol/L, p = 0.009). CONCLUSION: These results suggest that serum UA level can help to differentiate AIDP from A-CIDP with high specificity and sensitivity, which is helpful for early diagnosis and guidance of treatment.

GPR174 signals via Gαs to control a CD86-containing gene expression program in B cells.

GPR174 is abundantly expressed in B and T lymphocytes and has a role in restraining T cell responses, but the function of GPR174 in B cells is less clear. Here we report that upon in vitro culture B cells undergo a spontaneous GPR174-dependent activation process that is associated with marked changes in gene expression, including up-regulation of Cd86, Nr4a1, Ccr7, and phosphodiesterases. B cells lacking Gαs show a block in induction of the GPR174-dependent program. Spontaneous up-regulation of CD86 in cultured B cells is dependent on protein kinase A. Both GPR174- and Gαs-deficient B cells show enhanced survival in culture. In vivo, GPR174 contributes to NUR77 expression in follicular B cells and is needed for establishing a marginal zone compartment of normal size. Treatment of mice with lysophosphatidylserine (lysoPS), a GPR174 ligand, is sufficient to promote CD86 up-regulation by follicular B cells. These findings demonstrate that GPR174 can signal via Gαs to modulate B cell gene expression and show this can occur in vivo in response to lysoPS. Additionally, the findings illuminate a pathway that might be targeted to improve systems for the in vitro study of B cell responses.

Chemo- and mechanosensing by dendritic cells facilitate antigen surveillance in the spleen.

Spleen dendritic cells (DC) are critical for initiation of adaptive immune responses against blood-borne invaders. Key to DC function is their positioning at sites of pathogen entry, and their abilities to selectively capture foreign antigens and promptly engage T cells. Focusing on conventional DC2 (cDC2), we discuss the contribution of chemoattractant receptors (EBI2 or GPR183, S1PR1, and CCR7) and integrins to cDC2 positioning and function. We give particular attention to a newly identified role in cDC2 for adhesion G-protein coupled receptor E5 (Adgre5 or CD97) and its ligand CD55, detailing how this mechanosensing system contributes to splenic cDC2 positioning and homeostasis. Additional roles of CD97 in the immune system are reviewed. The ability of cDC2 to be activated by circulating missing self-CD47 cells and to integrate multiple red blood cell (RBC)-derived inputs is discussed. Finally, we describe the process of activated cDC2 migration to engage and prime helper T cells. Throughout the review, we consider the insights into cDC function in the spleen that have emerged from imaging studies.

CD97 promotes spleen dendritic cell homeostasis through the mechanosensing of red blood cells.

Dendritic cells (DCs) are crucial for initiating adaptive immune responses. However, the factors that control DC positioning and homeostasis are incompletely understood. We found that type-2 conventional DCs (cDC2s) in the spleen depend on Gα13 and adhesion G protein-coupled receptor family member-E5 (Adgre5, or CD97) for positioning in blood-exposed locations. CD97 function required its autoproteolytic cleavage. CD55 is a CD97 ligand, and cDC2 interaction with CD55-expressing red blood cells (RBCs) under shear stress conditions caused extraction of the regulatory CD97 N-terminal fragment. Deficiency in CD55-CD97 signaling led to loss of splenic cDC2s into the circulation and defective lymphocyte responses to blood-borne antigens. Thus, CD97 mechanosensing of RBCs establishes a migration and gene expression program that optimizes the antigen capture and presentation functions of splenic cDC2s.

Follicular dendritic cells restrict interleukin-4 availability in germinal centers and foster memory B cell generation.

B cells within germinal centers (GCs) enter cycles of antibody affinity maturation or exit the GC as memory cells or plasma cells. Here, we examined the contribution of interleukin (IL)-4 on B cell fate decisions in the GC. Single-cell RNA-sequencing identified a subset of light zone GC B cells expressing high IL-4 receptor-a (IL4Ra) and CD23 and lacking a Myc-associated signature. These cells could differentiate into pre-memory cells. B cell-specific deletion of IL4Ra or STAT6 favored the pre-memory cell trajectory, and provision of exogenous IL-4 in a wild-type context reduced pre-memory cell frequencies. IL-4 acted during antigen-specific interactions but also influenced bystander cells. Deletion of IL4Ra from follicular dendritic cells (FDCs) increased the availability of IL-4 in the GC, impaired the selection of affinity-matured B cells, and reduced memory cell generation. We propose that GC FDCs establish a niche that limits bystander IL-4 activity, focusing IL-4 action on B cells undergoing selection and enhancing memory cell differentiation.

The transcription factor Hhex cooperates with the corepressor Tle3 to promote memory B cell development.

Memory B cells (MBCs) are essential for long-lived humoral immunity. However, the transcription factors involved in MBC differentiation are poorly defined. Here, using single-cell RNA sequencing analysis, we identified a population of germinal center (GC) B cells in the process of differentiating into MBCs. Using an inducible CRISPR-Cas9 screening approach, we identified the hematopoietically expressed homeobox protein Hhex as a transcription factor regulating MBC differentiation. The corepressor Tle3 was also identified in the screen and was found to interact with Hhex to promote MBC development. Bcl-6 directly repressed Hhex in GC B cells. Reciprocally, Hhex-deficient MBCs exhibited increased Bcl6 expression and reduced expression of the Bcl-6 target gene Bcl2. Overexpression of Bcl-2 was able to rescue MBC differentiation in Hhex-deficient cells. We also identified Ski as an Hhex-induced transcription factor involved in MBC differentiation. These findings establish an important role for Hhex-Tle3 in regulating the transcriptional circuitry governing MBC differentiation.

PDGFRß Cells Rapidly Relay Inflammatory Signal from the Circulatory System to Neurons via Chemokine CCL2.

Acute infection, if not kept in check, can lead to systemic inflammatory responses in the brain. Here, we show that within 2 hr of systemic inflammation, PDGFRß mural cells of blood vessels rapidly secrete chemokine CCL2, which in turn increases total neuronal excitability by promoting excitatory synaptic transmission in glutamatergic neurons of multiple brain regions. By single-cell RNA sequencing, we identified Col1a1 and Rgs5 subgroups of PDGFRß cells as the main source of CCL2. Lipopolysaccharide (LPS)- or Poly(I:C)-treated pericyte culture medium induced similar effects in a CCL2-dependent manner. Importantly, in Pdgfrb-Cre;Ccl2fl/fl mice, LPS-induced increase in excitatory synaptic transmission was significantly attenuated. These results demonstrate in vivo that PDGFRß cells function as initial sensors of external insults by secreting CCL2, which relays the signal to the central nervous system. Through their gateway position in the brain, PDGFRß cells are ideally positioned to respond rapidly to environmental changes and to coordinate responses.

Phosphatidylinositol 3,4-bisphosphate regulates neurite initiation and dendrite morphogenesis via actin aggregation.

Neurite initiation is critical for neuronal morphogenesis and early neural circuit development. Recent studies showed that local actin aggregation underneath the cell membrane determined the site of neurite initiation. An immediately arising question is what signaling mechanism initiated actin aggregation. Here we demonstrate that local clustering of phosphatidylinositol 3,4-bisphosphate (PI(3,4)P2), a phospholipid with relatively few known signaling functions, is necessary and sufficient for aggregating actin and promoting neuritogenesis. In contrast, the related and more extensively studied phosphatidylinositol 4,5-bisphosphate or phosphatidylinositol (3,4,5)-trisphosphate (PIP3) molecules did not have such functions. Specifically, we showed that beads coated with PI(3,4)P2 promoted actin aggregation and neurite initiation, while pharmacological interference with PI(3,4)P2 synthesis inhibited both processes. PI(3,4)P2 clustering occurred even when actin aggregation was pharmacologically blocked, demonstrating that PI(3,4)P2 functioned as the upstream signaling molecule. Two enzymes critical for PI(3,4)P2 generation, namely, SH2 domain-containing inositol 5-phosphatase and class II phosphoinositide 3-kinase α, were complementarily and non-redundantly required for actin aggregation and neuritogenesis, as well as for subsequent dendritogenesis. Finally, we demonstrate that neural Wiskott-Aldrich syndrome protein and the Arp2/3 complex functioned downstream of PI(3,4)P2 to mediate neuritogenesis and dendritogenesis. Together, our results identify PI(3,4)P2 as an important signaling molecule during early development and demonstrate its critical role in regulating actin aggregation and neuritogenesis.

Predictors for vascular cognitive impairment in stroke patients.

BACKGROUND: Around two thirds stroke patients may suffer from vascular cognitive impairment (VCI). Our previous study has validated the NINDS-CSN harmonization standard for VCI diagnosis in Chinese. In this study, we aimed to investigate the predictors for VCI in Chinese post-stroke patients. METHODS: We compared epidemiological, clinical, and neuroimaging data (number, size and location of acute infarcts and lacunes, severities of white matter hyperintensities and brain atrophy) between stroke patients with and without VCI. Univariate and logistic regression analyses were utilized to determine VCI predictors. RESULTS: Fifty-six consecutive patients (age, 63.8 ± 8.3 years; female, 37.5%) were recruited at a mean interval of 7.1 months after stroke onset, and 31 (55.4%) patients were diagnosed with VCI based on a validated 60-min neuropsychological battery. VCI patients were older (p = 0.023), less educated (p = 0.001), more likely to be female (p < 0.001), had a recurrent stroke (p = 0.028), and described higher apathy (p = 0.022) and worse pre-stroke cognition (p = 0.048) than cognitively normal patients. Lower educational level (adjusted odds ratio [OR] 0.750, 95% confidence interval [CI], 0.573-0.981; p = 0.035), female sex (adjusted OR 8.288, 95% CI, 1.522-45.113; p = 0.014), recurrent stroke (adjusted OR 11.327, 95% CI, 1.335-96.130, p = 0.026), and global cortical atrophy (adjusted OR 5.730, 95% CI, 1.128-29.101, p = 0.035) were independently associated with VCI in post-stroke patients. CONCLUSIONS: Lower education, female sex, recurrent stroke and global cortical atrophy were associated with VCI in Chinese stroke patients.

Actin Aggregations Mark the Sites of Neurite Initiation.

A salient feature of neurons is their intrinsic ability to grow and extend neurites, even in the absence of external cues. Compared to the later stages of neuronal development, such as neuronal polarization and dendrite morphogenesis, the early steps of neuritogenesis remain relatively unexplored. Here we showed that redistribution of cortical actin into large aggregates preceded neuritogenesis and determined the site of neurite initiation. Enhancing actin polymerization by jasplakinolide treatment effectively blocked actin redistribution and neurite initiation, while treatment with the actin depolymerizing agents latrunculin A or cytochalasin D accelerated neurite formation. Together, these results demonstrate a critical role of actin dynamics and reorganization in neurite initiation. Further experiments showed that microtubule dynamics and protein synthesis are not required for neurite initiation, but are required for later neurite stabilization. The redistribution of actin during early neuronal development was also observed in the cerebral cortex and hippocampus in vivo.

Severity assessment of intracranial large artery stenosis by pressure gradient measurements: A feasibility study.

BACKGROUND: Fractional flow reserve (FFR)-guided revascularization strategy is popular in coronary intervention. However, the feasibility of assessing stenotic severity in intracranial large arteries using pressure gradient measurements still remains unclear. METHODS: Between March 2013 and May 2014, 12 consecutive patients with intracranial large artery stenosis (including intracranial internal carotid artery, middle cerebral M1 segment, intracranial vertebral artery, and basilar artery) were enrolled in this study. The trans-stenotic pressure gradient was measured before and/or after percutaneous transluminal angioplasty and stenting (PTAS), and was then compared with percent diameter stenosis. A Pd /Pa cut-off of ≤0.70 was used to guide stenting of hemodynamically significant stenoses. The device-related and procedure-related serious adverse events and recurrent cerebral ischemic events were recorded. RESULTS: The target vessel could be reached in all cases. No technical complications occurred due to the specific study protocol. Excellent pressure signals were obtained in all patients. For seven patients who performed PTAS, the mean pre-procedural pressure gradient decreased from 59.0 ± 17.2 to 13.3 ± 13.6 mm Hg after the procedure (P < 0.01). Only one patient who refused stenting experienced a TIA event in the ipsilateral MCA territory. No recurrent ischemic event was observed in other patients. CONCLUSION: Mean trans-stenotic pressure gradients can be safely and easily measured with a 0.014-inch fluid-filled guide wire in intracranial large arteries. © 2016 Wiley Periodicals, Inc.

Validation of NINDS-CSN neuropsychological battery for vascular cognitive impairment in Chinese stroke patients.

BACKGROUND: The NINDS-Canadian Stroke Network (NINDS-CSN) recommended a neuropsychological battery of three protocols to diagnose vascular cognitive impairment (VCI), however, due to culture and language differences, the battery cannot be directly used in China. Validation of the battery in mandarin Chinese is lacking. Our study investigated the reliability and validity of the adapted Chinese versions of the battery in stroke patients with high probability of VCI. METHODS: Fifty mild stroke patients (median of National Institute of Health Stroke Scale [NIHSS] score, 2) and 50 stroke-free normal controls were recruited. All subjects' demographics, clinical history, and stroke severity were recorded. The NINDS-CSN neuropsychological protocols were adapted into the Chinese versions. External validity, defined as the ability of the protocol summary scores to differentiate stroke patients from controls, was determined using the area under the curve (AUC) of the receiver operating characteristics curve. We also evaluated internal consistency and intra-rater reliability. RESULTS: Stroke patients performed significantly poorer than controls on all three protocols (F statistics between 24.9 and 31.4, P < 0.001). External validity evaluated by AUCs was 0.88 (95% confidence interval [CI], 0.81-0.95), 0.88 (95% CI, 0.81-0.94), and 0.86 (95% CI, 0.79-0.94) for the 60-min, 30-min and 5-min protocols, respectively. Cronbach's alpha of the cognitive tests was 0.87 for all subjects. Intra-rater reliability was acceptable with intraclass correlation coefficients 0.90, 0.83 and 0.75 for the 60-min, 30-min and 5-min protocols, respectively. CONCLUSIONS: The adapted Chinese versions of three NINDS-CSN neuropsychological protocols were valid and reliable for assessing VCI in Chinese patients with mild stroke.

Telephone-based cognitive screening for stroke patients in China.

BACKGROUND: Valid telephone assessment for cognitive impairment is lacking in stroke settings. We investigated the feasibility and validity of the 5-minute National Institute of Neurological Disorders and Stroke and Canadian Stroke Network (NINDS-CSN) protocol and six-item screener (SIS) in stroke patients by telephone administration. METHODS: Patients were assessed with a comprehensive face-to-face neuropsychological assessment after three months of stroke onset, followed by the 5-minute NINDS-CSN protocol (30 points) and SIS (6 points) at least one month later. Administration time was recorded for the telephone tests. Validity of both tests was determined using the area under the receiver operating characteristics curve (AUC). RESULTS: Eighty-nine patients (age, 62.9 ± 8.6 years; male, 65.2%) received a face-to-face assessment and 80 completed telephone tests. The time required to administer the 5-minute NINDS-CSN protocol was 4.3 ± 1.0 minutes, and SIS 57.3 ± 17.7 seconds. Validity of detecting cognitive impairment as assessed by AUC was 0.86 (95% CI, 0.78-0.94) for 5-minute NINDS-CSN protocol, and 0.74 (95% CI, 0.63-0.85) for SIS. Sensitivity and specificity were optimal with the cut-off values of 23.5/24 for the 5-minute NINDS-CSN protocol, and 4/5 for SIS. CONCLUSIONS: Both the telephone-based 5-minute NINDS-CSN protocol and SIS were feasible and valid in screening cognitive impairment after stroke in China.

From clinical to tissue-based dual TIA: Validation and refinement of ABCD3-I score.

OBJECTIVE: To investigate whether dual tissue-defined ischemic attacks, defined as multiple diffusion-weighted imaging lesions of different age and/or arterial territory (dual DWI), are an independent and stronger predictor of 90-day stroke than dual clinical TIAs (dual TIA). METHODS: Consecutive patients with clinically defined TIA were enrolled and assessed clinically and by MRI within 3 days. The predictive ability of the ABCD clinical factors, dual TIA, and dual DWI was evaluated by means of multivariate logistic regression. RESULTS: Among 658 patients who were included in the study and completed 90 days of follow-up, a total of 70 patients (10.6%) experienced subsequent stroke by 90 days. Multivariate logistic regression indicated that dual DWI was an independent predictor for subsequent stroke (odds ratio 4.64, 95% confidence interval 2.15-10.01), while dual TIA was not (odds ratio 1.18, 95% confidence interval 0.69-2.01). C statistics was higher when the item of dual TIA in ABCD3-I score was replaced by dual DWI (0.759 vs 0.729, p = 0.035). The net reclassification value for 90-day stroke risk was also improved (continuous net reclassification improvement 0.301, p = 0.017). CONCLUSION: Dual DWI independently predicted future stroke in patients with TIA. A new ABCD3-I score with dual DWI instead of dual clinical TIA may improve risk stratification for early stroke risk after TIA.

Association of chronic obstructive pulmonary disease with cognitive decline in very elderly men.

AIM: To determine the change in cognitive function in very elderly men with chronic obstructive pulmonary disease (COPD) over a 3-year period relative to age-and education-matched controls. METHODS: In this hospital-based, prospective case-control study, we evaluated a consecutive series of 110 very elderly men with COPD and 110 control subjects who were hospitalized between January and December 2007. All the subjects performed cognitive tests at baseline and underwent annual evaluations (for 3 years), which included the Mini-Mental State Examination, word list recall, delayed recall, animal category fluency, and the symbol digit modalities test. RESULTS: In mixed-effects models adjusted for hypertension and coronary heart disease, COPD was associated with a more rapid rate of cognitive decline based on the Mini-Mental State Examination, word list recall, delayed recall, animal category fluency, and the symbol digit modalities test (all p < 0.01) compared to controls. CONCLUSION: COPD is associated with a more rapid rate of cognitive decline in very elderly persons.

Cognitive functioning in elderly women who underwent unilateral oophorectomy before menopause.

The objective of this study is to compare differences in the cognitive functioning of elderly women who underwent unilateral oophorectomy before menopause with women who passed through natural menopause. A case-control study was conducted from December 2009 to August 2010. We studied the cognitive functioning of 50 elderly women who had undergone unilateral oophorectomy alone (20 cases) or with abdominal hysterectomy (30 cases) before menopause for a benign indication between May 1985 and December 1989. Tests of cognitive functioning were compared with results from 50 demographically matched control women. Test results for the unilateral oophorectomy group were lower than the control group, as measured on three separate trials for immediate and delayed word recall (p < .05). Hence we can conclude unilateral oophorectomy before menopause may have long-term deleterious effects on cognitive functioning in elderly women.

Association between mild parkinsonian signs and mortality in an elderly male cohort in China.

Our study aimed to examine the predictive role of mild parkinsonian signs (MPS) on mortality in an elderly male cohort. From January 2004, 1759 retired male military officers in Nanjing, China, underwent detailed clinical evaluations, which included assessments of MPS using an abbreviated Unified Parkinson's Disease Rating Scale at baseline. Data on deaths attributed to any cause were collected over a 4-year period of follow-up visits. Cox proportional hazard regression models were used to estimate the effect of MPS and chronic diseases on mortality. Of the 1759 participants, 278 (15.8%) had MPS at baseline. The participants with MPS and those without did not differ significantly with respect to the prevalence of chronic illness. The multivariate-adjusted relative risk of death (risk ratio, RR) for MPS was 1.77. After adjustment for the other MPS domains and chronic illnesses, only axial function abnormality was associated with an increased risk of death (RR 2.07). The presence of MPS in elderly subjects at baseline is a significant predictor of risk, even after adjustment for chronic illness.

[Characteristics of erectile dysfunction in old males with lacunar infarction].

OBJECTIVE: To investigate the characteristics of erectile dysfunction (ED) in old males with lacunar infarction. METHODS: A total of 38 old patients ages from 60 to 70 years were involved. The questionnaire of international index of erectile function 5 (IIEF -5) was used to determine the status and severity of ED. According to the focus of infarction on MRI, the patients were divided into two groups, Group I with lacunar infarction and minor neurological deficits, and Group II with none. The total IIEF-5 scores were compared between the two groups and repeatedly evaluated six months after discharge. RESULTS: According to the total scores of IIEF-5, the prevalence of ED in Group II (95%) was higher, and the incidence of severe ED was significantly increased (60.0% vs. 44.4%, P < 0.05) as compared with Group II. In both the two groups, severe ED was more often seen in diabetic patients. At six months after discharge, the total scores of IIEF-5 were significantly increased (11.2 +/- 3.2 vs. 15.6 +/- 2.2, P < 0.05). CONCLUSION: ED is significantly increased in old males with lacunar infarction, and it is more severe in diabetic patients. Post-stroke rehabilitation care helps to improve ED.