ISR inhibition reverses pancreatic ß-cell failure in Wolfram syndrome models.

Pancreatic ß-cell failure by WFS1 deficiency is manifested in individuals with wolfram syndrome (WS). The lack of a suitable human model in WS has impeded progress in the development of new treatments. Here, human pluripotent stem cell derived pancreatic islets (SC-islets) harboring WFS1 deficiency and mouse model of ß cell specific Wfs1 knockout were applied to model ß-cell failure in WS. We charted a high-resolution roadmap with single-cell RNA-seq (scRNA-seq) to investigate pathogenesis for WS ß-cell failure, revealing two distinct cellular fates along pseudotime trajectory: maturation and stress branches. WFS1 deficiency disrupted ß-cell fate trajectory toward maturation and directed it towards stress trajectory, ultimately leading to ß-cell failure. Notably, further investigation of the stress trajectory identified activated integrated stress response (ISR) as a crucial mechanism underlying WS ß-cell failure, characterized by aberrant eIF2 signaling in WFS1-deficient SC-islets, along with elevated expression of genes in regulating stress granule formation. Significantly, we demonstrated that ISRIB, an ISR inhibitor, efficiently reversed ß-cell failure in WFS1-deficient SC-islets. We further validated therapeutic efficacy in vivo with ß-cell specific Wfs1 knockout mice. Altogether, our study provides novel insights into WS pathogenesis and offers a strategy targeting ISR to treat WS diabetes.

Self-pulsing and dual-mode lasing in a square microcavity semiconductor laser.

Self-pulsing and dual-mode lasing in a square microcavity semiconductor laser are studied experimentally. Self-sustained pulses originating from undamped relaxation oscillation induced by a two-mode interaction are obtained, as the injection current is slightly above the laser threshold. A repetition frequency of 4.4 GHz and a pulse width of 30-40 ps are obtained at a current of 8 mA. The laser switches to continuous-wave operation when the injection current is higher than a certain value, and dual-mode lasing with 30.7 GHz at 16 mA and 10.7 GHz at 27 mA are observed in the lasing spectra. Furthermore, the relative intensity noise spectra are presented to reveal the relationship between the lasing states and the dynamics induced by relaxation oscillation and mode beating.

Narrow linewidth optical frequency comb based on a directly modulated microcavity laser with optical feedback.

A narrow linewidth optical frequency comb (OFC) based on a directly modulated microcavity laser with external optical feedback is investigated numerically and demonstrated experimentally. Based on the numerical simulations with rate equations, the evolution of the optical and electrical spectra is presented for the direct-modulated microcavity laser with increased feedback strength, and the linewidth property is improved at suitable feedback conditions. The simulation results also show good robustness for the generated OFC in terms of feedback strength and phase. Moreover, the OFC generation experiment is performed by combining with the dual-loop feedback structure to suppress the side mode, and an OFC with a side-mode suppression ratio of 31 dB is realized. Thanks to the high electro-optical response of the microcavity laser, a 15-tone OFC with a frequency interval of 10 GHz is obtained. Finally, the linewidth of each comb tooth is measured to be around 7 kHz under the feedback power of 47 µW, which indicates an enormous compression of approximately 2000 times compared with the free-running continuous-wave microcavity laser.

Effects of TCPP and TCEP exposure on human corneal epithelial cells: Oxidative damage, cell cycle arrest, and pyroptosis.

Tris(2-chloroisopropyl) phosphate (TCPP) and Tris(2-chloroethyl) phosphate (TCEP) are the widely used organophosphorus flame retardants indoors and easily accessible to the eyes as the common adhesive components of dust and particle matter, however, hardly any evidence has demonstrated their corneal toxicity. In this study, the adverse effects of TCPP, TCEP, and TCPP + TCEP exposure on human corneal epithelial cells (HCECs) were investigated. The cell viability and morphology, intracellular reactive oxygen species (ROS), cell cycle, and the expressions of cell cycle and pyroptosis-related genes were assessed to explain the underlying mechanisms. Compared to individual exposure, co-exposure to TCPP20+TCEP20 showed higher cytotoxicity with a sharp decrease of >30% in viability and more serious oxidative damage by increasing ROS production to 110.92% compared to the control group. Furthermore, the cell cycle arrested at the S phase (36.20%) was observed after combined treatment, evidenced by the upregulation of cyclin D1, CDK2, CDK4, CDK6, p21, and p27. Interestingly, pyroptosis-related genes GSDMD, Caspase-1, NLRP3, IL-1ß, IL-18, NLRP1, and NLRC4 expressions were promoted with cell swelling and glowing morphology. Oxidative stress and cell cycle arrest probably acted as a key role in TCPP20+TCEP20-induced cytotoxicity and pyroptosis in HCECs. Our results suggested that TCPP20+TCEP20 co-exposure induced severer corneal damage, further illustrating its significance in estimating indoor health hazards to humans.

Charting a high-resolution roadmap for regeneration of pancreatic ß cells by in vivo transdifferentiation from adult acinar cells.

Adult mammals have limited capacity to regenerate functional cells. Promisingly, in vivo transdifferentiation heralds the possibility of regeneration by lineage reprogramming from other fully differentiated cells. However, the process of regeneration by in vivo transdifferentiation in mammals is poorly understood. Using pancreatic ß cell regeneration as a paradigm, we performed a single-cell transcriptomic study of in vivo transdifferentiation from adult mouse acinar cells to induced ß cells. Using unsupervised clustering analysis and lineage trajectory construction, we uncovered that the cell fate remodeling trajectory was linear at the initial stage and the reprogrammed cells either evolved to induced ß cells or toward a "dead-end" state after day 4.Moreover, functional analyses identified both p53 and Dnmt3a that acted as reprogramming barriers during the process of in vivo transdifferentiation. Collectively, we decipher a high-resolution roadmap of regeneration by in vivo transdifferentiation and provide a detailed molecular blueprint to facilitate mammalian regeneration.

Thermogenic adipocyte-derived zinc promotes sympathetic innervation in male mice.

Sympathetic neurons activate thermogenic adipocytes through release of catecholamine; however, the regulation of sympathetic innervation by thermogenic adipocytes is unclear. Here, we identify primary zinc ion (Zn) as a thermogenic adipocyte-secreted factor that promotes sympathetic innervation and thermogenesis in brown adipose tissue and subcutaneous white adipose tissue in male mice. Depleting thermogenic adipocytes or antagonizing ß3-adrenergic receptor on adipocytes impairs sympathetic innervation. In obesity, inflammation-induced upregulation of Zn chaperone protein metallothionein-2 decreases Zn secretion from thermogenic adipocytes and leads to decreased energy expenditure. Furthermore, Zn supplementation ameliorates obesity by promoting sympathetic neuron-induced thermogenesis, while sympathetic denervation abrogates this antiobesity effect. Thus, we have identified a positive feedback mechanism for the reciprocal regulation of thermogenic adipocytes and sympathetic neurons. This mechanism is important for adaptive thermogenesis and could serve as a potential target for the treatment of obesity.

Modeling disrupted synapse formation in wolfram syndrome using hESCs-derived neural cells and cerebral organoids identifies Riluzole as a therapeutic molecule.

Dysregulated neurite outgrowth and synapse formation underlie many psychiatric disorders, which are also manifested by wolfram syndrome (WS). Whether and how the causative gene WFS1 deficiency affects synapse formation remain elusive. By mirroring human brain development with cerebral organoids, WFS1-deficient cerebral organoids not only recapitulate the neuronal loss in WS patients, but also exhibit significantly impaired synapse formation and function associated with reduced astrocytes. WFS1 deficiency in neurons autonomously delays neuronal differentiation with altered expressions of genes associated with psychiatric disorders, and impairs neurite outgrowth and synapse formation with elevated cytosolic calcium. Intriguingly, WFS1 deficiency in astrocytes decreases the expression of glutamate transporter EAAT2 by NF-κB activation and induces excessive glutamate. When co-cultured with wildtype neurons, WFS1-deficient astrocytes lead to impaired neurite outgrowth and increased cytosolic calcium in neurons. Importantly, disrupted synapse formation and function in WFS1-deficient cerebral organoids and impaired neurite outgrowth affected by WFS1-deficient astrocytes are efficiently reversed with Riluzole treatment, by restoring EAAT2 expression in astrocytes. Furthermore, Riluzole rescues the depressive-like behavior in the forced swimming test and the impaired recognition and spatial memory in the novel object test and water maze test in Wfs1 conditional knockout mice. Altogether, our study provides novel insights into how WFS1 deficiency affects synapse formation and function, and offers a strategy to treat this disease.

Indoor air pollution and human ocular diseases: Associated contaminants and underlying pathological mechanisms.

People spend a long time indoors, especially young children. The risk of indoor pollution on human health is one of the current hotspots in environmental and public health. The human ocular surface is highly susceptible to indoor environment quality. Epidemiological data have linked human ophthalmological disorders with exposure to indoor pollution. In this review, we summarized the adverse impacts of indoor pollution on the human ocular surface. Several studies demonstrated that indoor contaminants including particulate matter, volatile/semi-volatile organic compounds, heavy metals, and fuel combustion and cigarette smoke exposure were associated with the incidence of human dry eye, conjunctivitis, glaucoma, cataracts, age-related macular degeneration, and keratitis. In addition, toxicological investigations revealed that indoor pollution-induced induced chronic inflammation, oxidative damage, and disruption of tight junctions are the main underlying pathological mechanisms for ocular surface diseases. Taken together, this review may expand the understanding of pollution-induced eye disorder and highlight the importance of reducing associated contaminants to decrease their detrimental effects on human eyes.

Nonlinear dynamics of a semiconductor microcavity laser subject to frequency comb injection.

The nonlinear dynamical behaviors of a semiconductor microcavity laser with frequency comb injection have been experimentally and numerically investigated. The microcavity laser is harmonically locked to a unit fraction of the comb spacing due to the undamped relaxation oscillation at certain conditions, creating additional comb lines with reduced frequency spacing. The stability maps indicating various locking states are obtained based on rate equations, which demonstrates that the locking regions are closely related to the relaxation oscillation. Moreover, the microcavity laser with comb injection leads to spectral broadening of the original comb and the number of comb lines raises from 3 to 13. Owing to the large modulation bandwidth of the microcavity laser, the comb lines and the frequency spacing can be tailored over a wide range by varying the injection parameters.

Effects of Nickel at Environmentally Relevant Concentrations on Human Corneal Epithelial Cells: Oxidative Damage and Cellular Apoptosis.

Nickel (Ni) is ubiquitous in the environment and evidence has suggested that Ni can cause ocular surface inflammation, especially in fine particulate matter and personal products. Continuous daily exposure to Ni-containing dust may adversely impact the human cornea, whereas the underlying mechanism of this phenomenon remains not fully understood. Here, human corneal epithelial cells (HCEC) were employed to analyze the toxicity of Ni via detections of cell morphology, cell viability, reactive oxygen species production, cell apoptosis rate, and apoptotic gene expression levels after exposure for 24 h to uncover the damage of Ni to the cornea. A concentration-dependent inhibition of HCECs' viability and growth was observed. In particular, Ni at 100 µM significantly decreased cell viability to 76%, and many cells displayed an abnormal shape and even induced oxidative damage of HCEC by increasing ROS to 1.2 times, and further led to higher apoptosis (24%), evidenced by up-regulation of apoptotic genes Caspase-8, Caspase-9, NF-κB, IL-1ß, and Caspase-3, posing a risk of dry eye. Our study suggested that Ni induces apoptosis of HCEC through oxidative damage. Therefore, Ni pollution should be comprehensively considered in health risks or toxic effects on the ocular surface.

Hepatic ER stress suppresses adipose browning through ATF4-CIRP-ANGPTL3 cascade.

Hepatic endoplasmic reticulum (ER) stress is a hallmark of obesity-induced liver steatosis and contributes to the progress of steatosis and insulin resistance in liver. However, its influence on adipose function is still unclear. Here, we identify a hepatic ER stress-induced activating transcription factor 4 (ATF4)-cold-inducible RNA-binding protein (CIRP)-angiopoietin-related protein3 (ANGPTL3) cascade critical for the regulation of adipose browning. We find that obesity increases CIRP expression in liver through ER stress-induced ATF4. CIRP in turn binds to the 3' UTR and increases mRNA stability of ANGPTL3. ANGPTL3 secreted from liver suppresses uncoupling protein 1 expression through integrin αvß3 and c-Jun N-terminal kinase in adipose tissue. While hepatic expression of either ATF4, CIRP, or ANGPTL3 suppresses adipose browning, knockdown of CIRP and ANGPTL3 in liver or administration of integrin αvß3 inhibitor cilengitide increases adipose browning process. Taken together, we identify a communication mechanism to link hepatic ER stress and adipose browning that may imply a reciprocal regulation of obesity and liver steatosis.

[Chiropractic plus plum-blossom needling combined with flexibility training on attention deficit in mentally-retarded adolescents].

OBJECTIVE: To observe the clinical efficacy of chiropractic plus plum-blossom needling combined with flexibility training for attention deficit in mentally-retarded adolescents. METHODS: Thirty adolescents with mild mental retardation were randomly divided into a medical rehabilitation plus flexibility training group (10 cases, 2 cases dropped off), a flexibility training group (10 cases, 1 case dropped off) and a control group (10 cases). The patients in the flexibility training group received flexibility training, once every other day, 3 times a week for 12 weeks. The patients in the medical rehabilitation plus flexibility training group received chiropractic and plum-blossom needling at Baihui (GV 20) and Sishencong (EX-HN 1) on the basis of the treatment in the flexibility training group, once every other day, 3 times a week for 12 weeks. The patients in the control group did not receive any targeted physical training and medical rehabilitation. Tobii Pro Spectrum eye movement instrument was used to test the attention concentration (T), attention span (M), attention transfer (γ%) and attention distribution (η). RESULTS: Compared before treatment, T and M in the medical rehabilitation plus flexibility training group and the flexibility training group were increased after treatment (P<0.01, P<0.05), and γ% in the medical rehabilitation plus flexibility training group was increased after treatment (P<0.05). The increasing range of T, M and γ% in the medical rehabilitation plus flexibility training group and the flexibility training group was greater than that in the control group (P<0.01), and the increasing range of T and γ% in the medical rehabilitation plus flexibility training group was greater than that in the flexibility training group (P<0.05). CONCLUSION: The chiropractic plus plum blossom needling combined with flexibility training can improve the attention deficit in mentally-retarded adolescents.

ZnT8 loss-of-function accelerates functional maturation of hESC-derived ß cells and resists metabolic stress in diabetes.

Human embryonic stem cell-derived ß cells (SC-ß cells) hold great promise for treatment of diabetes, yet how to achieve functional maturation and protect them against metabolic stresses such as glucotoxicity and lipotoxicity remains elusive. Our single-cell RNA-seq analysis reveals that ZnT8 loss of function (LOF) accelerates the functional maturation of SC-ß cells. As a result, ZnT8 LOF improves glucose-stimulated insulin secretion (GSIS) by releasing the negative feedback of zinc inhibition on insulin secretion. Furthermore, we demonstrate that ZnT8 LOF mutations endow SC-ß cells with resistance to lipotoxicity/glucotoxicity-triggered cell death by alleviating endoplasmic reticulum (ER) stress through modulation of zinc levels. Importantly, transplantation of SC-ß cells with ZnT8 LOF into mice with preexisting diabetes significantly improves glycemia restoration and glucose tolerance. These findings highlight the beneficial effect of ZnT8 LOF on the functional maturation and survival of SC-ß cells that are useful as a potential source for cell replacement therapies.

Targeting parvalbumin promotes M2 macrophage polarization and energy expenditure in mice.

Exercise benefits M2 macrophage polarization, energy homeostasis and protects against obesity partially through exercise-induced circulating factors. Here, by unbiased quantitative proteomics on serum samples from sedentary and exercised mice, we identify parvalbumin as a circulating factor suppressed by exercise. Parvalbumin functions as a non-competitive CSF1R antagonist to inhibit M2 macrophage activation and energy expenditure in adipose tissue. More importantly, serum concentrations of parvalbumin positively correlate with obesity in mouse and human, while treating mice with a recombinant parvalbumin blocker prevents its interaction with CSF1R and promotes M2 macrophage polarization and ameliorates diet-induced obesity. Thus, although further studies are required to assess the significance of parvalbumin in mediating the effects of exercise, our results implicate parvalbumin as a potential therapeutic strategy against obesity in mice.

Manipulation of lasing modes in a circular-side octagonal microcavity laser with a spatially distributed current injection.

We propose and demonstrate a circular-side octagonal microcavity (COM) semiconductor laser with a spatially distributed current injection for manipulating the lasing modes. There are two types of high-quality-factor whispering-gallery (WG) modes with distinct field patterns in a COM: the four-bounced quadrilateral modes and the eight-bounced octagonal modes. By designing two separated p-electrodes, the COM laser is divided into two regions that are pumped independently to select specific modes for lasing. The two types of WG modes lase simultaneously when the two regions are injected with equivalent currents. Degeneracy removal of the quadrilateral modes is observed in both simulation and experiment when the two regions are injected with inequivalent currents. The quadrilateral modes are suppressed when one of the two regions is un-injected or biased with a negative current, and single-octagonal-mode lasing is realized. The results show that the lasing modes can be efficiently manipulated with the spatially distributed current injection considering the distinct field patterns of different WG modes in the microcavities, which can promote the practical application of the microcavity lasers.

[Abdominal acupoint thread embedding therapy based on "brain-intestinal connection" for mild-to-moderate Alzheimer's disease and its effects on serum levels of APP and Aß1-42].

OBJECTIVE: To compare the clinical efficacy of abdominal acupoint thread embedding therapy based on "brain-intestinal connection" combined with donepezil hydrochloride tablets and oral donepezil hydrochloride tablets alone for mild-to-moderate Alzheimer's disease (AD) and observe its effects on amyloid precursor protein (APP) and ß-amyloid protein1-42 (Aß1-42). METHODS: Sixty patients with AD were randomly divided into an observation group (30 cases, 3 cases dropped off) and a control group (30 cases, 3 cases dropped off). The patients in the control group were treated with donepezil hydrochloride tablets (5 mg per day); based on the treatment in the control group, the patients in the observation group were treated with abdominal acupoint thread embedding therapy at Zhongwan (CV 12), Xiawan (CV 10), Huaroumen (ST 24), Wailing (ST 26), Daheng (SP 15), etc., once every 10 days. Both groups were treated for 2 months. The mini-mental state examination (MMSE), Alzheimer's disease assessment scale-cognitive subscale (ADAS-Cog), activity of daily living scale (ADL), neuropsychiatric inventory questionnaire (NPI) as well as the serum levels of APP and Aß1-42 were observed before and after treatment in the two groups. RESULTS: After treatment, the MMSE scores in the two groups were higher than those before treatment (P<0.05), and the ADAS-Cog, ADL and NPI scores were lower than those before treatment (P<0.05). After treatment, the MMSE score in the observation group was higher than that in the control group (P<0.05), and the ADAS-Cog, ADL and NPI scores were lower than those in the control group (P<0.05). After treatment, the serum levels of APP and Aß1-42 were lower than those before treatment (P<0.05), and the serum levels of APP and Aß1-42 in the observation group was lower than those in the control group (P<0.05). CONCLUSION: The abdominal acupoint thread embedding therapy based on the theory of "brain-intestinal connection" combined with donepezil hydrochloride tablets can improve cognitive function, self-care ability of daily life and mental behavior, and reduce the serum levels of APP and Aß1-42 in patients with mild-to-moderate AD, which have superior clinical effect to donepezil hydrochloride tablets alone.

MiniCAFE, a CRISPR/Cas9-based compact and potent transcriptional activator, elicits gene expression in vivo.

CRISPR-mediated gene activation (CRISPRa) is a promising therapeutic gene editing strategy without inducing DNA double-strand breaks (DSBs). However, in vivo implementation of these CRISPRa systems remains a challenge. Here, we report a compact and robust miniCas9 activator (termed miniCAFE) for in vivo activation of endogenous target genes. The system relies on recruitment of an engineered minimal nuclease-null Cas9 from Campylobacter jejuni and potent transcriptional activators to a target locus by a single guide RNA. It enables robust gene activation in human cells even with a single DNA copy and is able to promote lifespan of Caenorhabditis elegans through activation of longevity-regulating genes. As proof-of-concept, delivered within an all-in-one adeno-associated virus (AAV), miniCAFE can activate Fgf21 expression in the liver and regulate energy metabolism in adult mice. Thus, miniCAFE holds great therapeutic potential against human diseases.

Sequential fate-switches in stem-like cells drive the tumorigenic trajectory from human neural stem cells to malignant glioma.

Glioblastoma (GBM) is an incurable and highly heterogeneous brain tumor, originating from human neural stem/progenitor cells (hNSCs/hNPCs) years ahead of diagnosis. Despite extensive efforts to characterize hNSCs and end-stage GBM at bulk and single-cell levels, the de novo gliomagenic path from hNSCs is largely unknown due to technical difficulties in early-stage sampling and preclinical modeling. Here, we established two highly penetrant hNSC-derived malignant glioma models, which resemble the histopathology and transcriptional heterogeneity of human GBM. Integrating time-series analyses of whole-exome sequencing, bulk and single-cell RNA-seq, we reconstructed gliomagenic trajectories, and identified a persistent NSC-like population at all stages of tumorigenesis. Through trajectory analyses and lineage tracing, we showed that tumor progression is primarily driven by multi-step transcriptional reprogramming and fate-switches in the NSC-like cells, which sequentially generate malignant heterogeneity and induce tumor phenotype transitions. We further uncovered stage-specific oncogenic cascades, and among the candidate genes we functionally validated C1QL1 as a new glioma-promoting factor. Importantly, the neurogenic-to-gliogenic switch in NSC-like cells marks an early stage characterized by a burst of oncogenic alterations, during which transient AP-1 inhibition is sufficient to inhibit gliomagenesis. Together, our results reveal previously undercharacterized molecular dynamics and fate choices driving de novo gliomagenesis from hNSCs, and provide a blueprint for potential early-stage treatment/diagnosis for GBM.

Organophosphorus flame retardant TDCPP-induced cytotoxicity and associated mechanisms in normal human skin keratinocytes.

Tris(1,3-dichloro-2-propyl) phosphate (TDCPP), a widely used organophosphorus flame retardant, has been frequently detected in the environment including indoor dust. Long-term exposure to TDCPP-containing dust may adversely affect human skin, however, little is known about its potential cytotoxicity. In this study, human skin keratinocytes (HaCaT) were employed to study TDCPP-induced cytotoxicity and associated mechanisms. The effects of TDCPP on cell morphology, viability, apoptosis, and cycle, and the mRNA levels of apoptosis (Bcl-2, Bax and Caspase-3) and cell cycle (cyclin D1, CDK2, CDK4 and CDK6) regulatory genes were investigated. The results showed that TDCPP caused a concentration-dependent decrease in cell viability after exposing to TDCPP ≥100 µg/mL for 48 h, with a median lethal concentration of 163 µg/mL (LC50). In addition, TDCPP induced cell apoptosis and arrested cell cycle in the G0/G1 phase at 16 and 160 µg/mL by enhancing Bax and Caspase-3 expression besides inhibiting cyclin D1, CDK2, CDK6 and Bcl-2 expression. Our results showed that TDCPP-induced toxicity in HaCaT cells was probably through cell apoptosis and cell cycle arrest. This study provides information on the toxicity of TDCPP to human skin cells, which may help to reduce its toxicity to human skin.