Chromone-deferiprone hybrids as novel MAO-B inhibitors and iron chelators for the treatment of Alzheimer's disease.

A series of chromone-deferiprone hybrids were designed, synthesized, and evaluated as inhibitors of human monoamine oxidase B (hMAO-B) with iron-chelating activity for the treatment of Alzheimer's disease (AD). The majority exhibited moderate inhibitory activity towards hMAO-B and potent iron-chelating properties. Particularly, compound 25c demonstrated remarkable selectivity against hMAO-B with an IC50 value of 1.58 µM and potent iron-chelating ability (pFe3+ = 18.79) comparable to that of deferiprone (pFe3+ = 17.90). Molecular modeling and kinetic studies showed that 25c functions as a non-competitive hMAO-B inhibitor. According to the predicted results, compound 25c can penetrate the blood-brain barrier (BBB). Additionally, it has been proved to display significant antioxidant activity and the ability to inhibit neuronal ferroptosis. More importantly, compound 25c reduced the cognitive impairment induced by scopolamine and showed significant non-toxicity in short-term toxicity assays. In summary, compound 25c was identified as a potential anti-AD agent with hMAO-B inhibitory, iron-chelating and anti-ferroptosis activities.

Photodynamic anticancer activity evaluation of novel 5-aminolevulinic acid and 3-hydroxypyridinone conjugates.

5-Aminolevulinic acid (ALA) and its derivatives, serving as the endogenous precursor of the photosensitizer (PS) protoporphyrin IX (PpIX), successfully applied in tumor imaging and photodynamic therapy (PDT). ALA and its derivatives have been used to treat actinic keratosis (AK), basal cell carcinoma (BCC), and improve the detection of superficial bladder cancer. However, the high hydrophilicity of ALA and the conversion of PpIX to heme have limited the accumulation of PpIX, hindering the efficiency and potential application of ALA-PDT. This study aims to evaluate the PDT activity of three rationally designed series of ALA-HPO prodrugs, which were based on enhancing the lipophilicity of the prodrugs and reducing the labile iron pool (LIP) through HPO iron chelators to promote PpIX accumulation. Twenty-four ALA-HPO conjugates, incorporating amide, amino acid, and ester linkages, were synthesized. Most of the conjugates, exhibited no dark-toxicity to cells, according to bioactivity evaluation. Ester conjugates 19a-g showed promoted phototoxicity when tested on tumor cell lines, and this increased phototoxicity was strongly correlated with elevated PpIX levels. Among them, conjugate 19c emerged as the most promising (HeLa, IC50 = 24.25 ± 1.43 µM; MCF-7, IC50 = 43.30 ± 1.76 µM; A375, IC50 = 28.03 ± 1.00 µM), displaying superior photodynamic anticancer activity to ALA (IC50 > 100 µM). At a concentration of 80 µM, the fluorescence intensity of PpIX induced by compound 19c in HeLa, MCF-7, and A375 cells was 18.9, 5.3, and 2.8 times higher, respectively, than that induced by ALA. In conclusion, cellular phototoxicity showed a strong correlation with intracellular PpIX fluorescence levels, indicating the potential application of ALA-HPO conjugates in ALA-PDT.

Identification of a novel intronic mutation of MAGED2 gene in a Chinese family with antenatal Bartter syndrome.

BACKGROUND: Antenatal Bartter syndrome is a life-threatening disease caused by a mutation in the MAGED2 gene located on chromosome Xp11. It is characterized by severe polyhydramnios and extreme prematurity. While most reported mutations are located in the exon region, variations in the intron region are rarely reported. METHODS: In our study, we employed whole exome sequencing and Sanger sequencing to genotype members of this family. Additionally, a minigene assay was conducted to evaluate the impact of genetic variants on splicing. RESULTS: Our findings reveal a novel intronic variant (NM_177433.3:c.1271 + 4_1271 + 7delAGTA) in intron 10 of the MAGED2 gene. Further analysis using the minigene assay demonstrated that this variant activated an intronic cryptic splice site, resulting in a 96 bp insertion in mature mRNA. CONCLUSIONS: Our results indicate that the novel intronic variant (c.1271 + 4_1271 + 7delAGTA) in intron 10 of the MAGED2 gene is pathogenic. This expands the mutation spectrum of MAGED2 and highlights the significance of intronic sequence analysis.

Chronic Sleep Deprivation Impairs Visual Functions via Oxidative Damage in Mice.

Sleep deprivation (SD) is a global public health burden, and has a detrimental role in the nervous system. Retina is an important part of the central nervous system; however, whether SD affects retinal structures and functions remains largely unknown. Herein, chronic SD mouse model indicated that loss of sleep for 4 months could result in reductions in the visual functions, but without obvious morphologic changes of the retina. Ultrastructural analysis by transmission electron microscope revealed the deterioration of mitochondria, which was accompanied with the decrease of multiple mitochondrial proteins in the retina. Mechanistically, oxidative stress was provoked by chronic SD, which could be ameliorated after rest, and thus restore retinal homeostasis. Moreover, the supplementation of two antioxidants, α-lipoic acid and N-acetyl-l-cysteine, could reduce retinal reactive oxygen species, repair damaged mitochondria, and, as a result, improve the retinal functions. Overall, this work demonstrated the essential roles of sleep in maintaining the integrity and health of the retina. More importantly, it points towards supplementation of antioxidants as an effective intervention strategy for people experiencing sleep shortages.

REG1A protects retinal photoreceptors from blue light damage.

With the increased use of artificial light and the prolonged use of optoelectronic products, light damage (LD) to the human retina has been identified as a global vision-threatening problem. While there is evidence of a significant correlation between light-induced retinal damage and age-related vision impairment in age-related macular degeneration, it is unclear how light-induced retinal degeneration manifests itself and whether there are agents capable of preventing the development of LD in the retina. This study investigated a mechanism by which blue light leads to photoreceptor death. By observing blue light exposure in retinal organoids and photoreceptor cells, we concluded that there could be significant apoptosis of the photoreceptors. We demonstrate that regenerating islet-derived 1 alpha (REG1A) prevents photoreceptors from undergoing this LD-induced apoptosis by increasing expression of the anti-apoptotic gene Bcl2 and downregulating expression of the pro-apoptotic gene Bax, resulting in reduced mitochondrial damage and improved aerobic capacity in photoreceptor cells. For the first time, REG1A has been shown to restore mitochondrial function and cell apoptosis after LD-induced damage, suggesting its potential application in the prevention and treatment of retinal vision loss.

Comparison the effects of progestin-primed ovarian stimulation (PPOS) protocol and GnRH-a long protocol in patients with normal ovarian reserve function.

OBJECTIVE: To compare the effects of progestin-primed ovarian stimulation (PPOS) protocol and GnRH-a long protocol in infertility patients with normal ovarian reserve function undergoing invitro fertilization and embryo transfer. METHODS: A retrospective cohort study was conducted to analyze the clinical data of 2013 cycles of patients with normal ovarian reserve function who underwent invitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET) in the Department of Human Reproductive Center, Renmin Hospital, Hubei University of Medicine from January 2018 and June 2020. The PPOS protocol group included 679 cycles and GnRH-along protocol group included 1334 cycles, the pregnancy outcomes were compared between the two groups. RESULTS: The duration of Gn used and total Gn used dosage in the PPOS protocol group were less than those in the GnRH-along protocol group (Duration of Gn used: 10.05 ± 1.48 vs 11.90 ± 1.85 d, p < 0.001; Total Gn used dosage: 1944.49 ± 533.61 vs 2661.34 ± 987.97 IU, p < 0.001); The LH levels were significantly higher on HCG trigger day in PPOS protocol compared to GnRH-a long protocol (2.8 ± 1 ± 1.07 vs 1.01 ± 0.62 IU/L, p < 0.001), the E2 levels on HCG trigger day in PPOS protocol group was lower than that in the GnRH-a long protocol group (2135.92 ± 1387.00 vs 2417.01 ± 1010.70 pg/mL, p < 0. 001). The number of oocytes retrieved in the PPOS protocol group was lower than that in the GnRH-along protocol group (8.03 ± 2.86 vs 9.47 ± 2.64, p < 0.001). No significant differences were found in pregnancy outcome including clinical pregnancy rate, early miscarriage rate and ectopic pregnancy rate between the two group (p > 0.05); In addition, no severe OHSS occurred in the PPOS protocol group during ovulation induction, while 11 patients of severe ovarian hyperstimulation syndrome (OHSS) occurred in GnRH-a long protocol group (p < 0.001). CONCLUSION: The clinical efficacy of PPOS protocol combining embryo cryopreservation is comparable to that of GnRH-a long protocol in patients with normal ovarian reserve function, and the PPOS protocol is able to reduce the incidence of severe OHSS significantly.

The serum oestradiol/progesterone ratio on the day of OPU + 7, but not the day of OPU + 5, affects the rates of live birth in fresh blastocyst embryo transfer cycles.

BACKGROUND: In an in vitro fertilization (IVF) cycle, the embryo ends its wandering time and begins the process of implantation into the uterine cavity on the seventh day after oocyte pick-up (OPU + 7), which is closer than OPU + 5 to the time of nidation. Therefore, measuring the oestradiol (E2)/progesterone (P) ratio on OPU + 7 may be helpful for predicting pregnancy outcomes. METHODS: This is a retrospective cohort study of 2,257 women undergoing a follicular-phase depot gonadotropin-releasing hormone agonist (GnRH-a) protocol for in vitro fertilization /intracytoplasmic sperm injection (IVF/ICSI) treatment and fresh blastocyst embryo transfer cycles at a university-affiliated fertility center between January 2016 and April 2021. First, 2,257 women were split into two groups based on clinical pregnancy for analyzing the levels of E2 and P and the E2/P ratio on the day of OPU + 2, OPU + 5 and OPU + 7. And then 2,257 cycles were stratified into three groups based on E2/P ratio tertiles on OPU + 7: the low group (1.3-15.7 pg/ng), middle group (15.7-28.8 pg/ng), and high group (28.8-487.2 pg/ng). The threshold effect of the E2/P ratio on OPU + 7 on live birth was investigated using a two-piecewise linear regression model and a smoothing function curve. RESULTS: The level of P in the clinical pregnancy group were lower than that in the nonclinical pregnancy group on both OPU + 2 and OPU + 7 (201.9 ± 71.6 ng/ml vs 213.1 ± 77.6 ng/ml, 89.5 ± 88.5 ng/ml vs 99.5 ± 94.9 ng/ml, P < 0.05). The E2/P ratio in the clinical pregnancy group were higher than that in the nonclinical pregnancy group on both OPU + 2 and OPU + 7 (8.4 ± 6.5 pg/ng vs 8.0 ± 6.8 pg/ng, 32.3 ± 38.5 pg/ng vs 25.2 ± 31.0 pg/ng, P < 0.01). The E2/P ratio on OPU + 7 was positively associated with positive hCG (adjusted OR = 1.01; 95% CI, 1.01-1.02; P < 0.0001), clinical pregnancy (adjusted OR = 1.01; 95% CI, 1.00-1.01; P = 0.0067) and live birth (adjusted OR = 1.01; 95% CI, 1.00-1.01; P < 0.001), and a nonlinear correlation was observed between the E2/P ratio and LBR on OPU + 7. CONCLUSIONS: A higher E2/P ratio is associated with a higher LBR, but the E2/P ratio should be maintained within a suitable range.

Chromone-based monoamine oxidase B inhibitor with potential iron-chelating activity for the treatment of Alzheimer's disease.

Based on the multitarget-directed ligands (MTDLs) strategy, a series of chromone-hydroxypyridinone hybrids were designed, synthesised, and evaluated as potential multimodal anti-AD ligands. Prospective iron-chelating effects and favourable monoamine oxidase B (MAO-B) inhibitory activities were observed for most of the compounds. Pharmacological assays led to the identification of compound 17d, which exhibited favourable iron-chelating potential (pFe3+ = 18.52) and selective hMAO-B inhibitory activity (IC50 = 67.02 ± 4.3 nM, SI = 11). Docking simulation showed that 17d occupied both the substrate and the entrance cavity of MAO-B, and established several key interactions with the pocket residues. Moreover, 17d was determined to cross the blood-brain barrier (BBB), and can significantly ameliorate scopolamine-induced cognitive impairment in AD mice. Despite its undesired pharmacokinetic property, 17d remains a promising multifaceted agent that is worth further investigation.

Effect of TSH on oocyte maturation of PCOS patients with normal thyroid function in IVF.

BACKGROUND: The serum TSH level of PCOS patients was higher than that of the general female population. For patients with thyroid dysfunction, the abnormal TSH level is negatively related to the outcomes of assisted reproductive technology, but for PCOS patients with normal thyroid function, the effect of TSH level on outcomes of in vitro fertilization has not been reported. In this study, PCOS patients with normal thyroid function were included in this study to evaluate the effect of TSH on the outcomes of IVF-ET. METHODS: A retrospective cohort study was conducted to analyze the clinical data of 3190 patients who underwent IVF-ET in the Department of Human Reproductive Center of Renmin Hospital Hubei University of Medicine from January 2017 to July 2021, including 594 PCOS patients and 2595 non PCOS patients. The IVF-ET outcomes between the two groups were compared; Multi-factor linear regression analysis was used to analyze the correlation between the related variables and the oocyte maturation of PCOS patients; The ROC curve of the effect of TSH on oocyte maturation in PCOS patients was drawn. The PCOS patients were divided into TSH < 2.98 group (n = 454) and TSH ≥ 2.98 group (n = 141) according to ROC threshold TSH 2.98, and the outcomes were compared. RESULTS: TSH level in PCOS group was significantly higher than that in non-PCOS group (2.42 ± 0.86 vs 2.00 ± 0.89 UU / ml, P < 0.01), and the oocyte maturation rate and 2PN fertilization rate in PCOS group were lower than those in non-PCOS group (90.9% vs 92.4%, P = 0.02) (84.57% vs 86.77%, P = 0.02). There was no significant difference in cleavage rate and high-quality embryo rate between the two groups (P > 0.05); There was no difference in clinical pregnancy rate, abortion rate, ectopic pregnancy rate and live birth rate between the two groups (P > 0.05). Multi-factor linear regression analysis showed that TSH was negatively correlated with oocyte maturation in PCOS patients [ß = -0.124, P = 0.013,95%CI (-0.027 ~ -0.003)]; The oocyte maturation rate in TSH < 2.98 group was significantly higher than that in TSH ≥ 2.98 group (91.7% vs 88.2%, P = 0.001). CONCLUSION: The TSH level of PCOS patients with normal thyroid function is higher than that of normal people, and it is negatively correlated with the oocyte maturation in in-vitro fertilization. The ROC curve showed that when TSH > 2.98uIU/ml, the possibility of immature oocytes was higher (specificity 28.9%, sensitivity 83.0%).

The follicular-phase depot GnRH agonist protocol results in a higher live birth rate without discernible differences in luteal function and child health versus the daily mid-luteal GnRH agonist protocol: a single-centre, retrospective, propensity score matched cohort study.

BACKGROUND: The gonadotropin-releasing hormone agonist (GnRH-a) has been used in in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycles for a long time. This paper evaluates the efficacy and safety of two commonly used protocols (follicular-phase depot GnRH-a protocol and daily mid-luteal long GnRH-a protocol) in normal responders undergoing IVF/ICSI using propensity score matching (PSM) analysis. METHODS: A total of 6,816 infertile women treated within the period from January 2016 to September 2020 were stratified into cohorts. A total of 2,851 patients received the long-acting group (depot GnRH-a protocol), and 1,193 used the short-acting group (long GnRH-a protocol) after the data-selection process. PSM was utilized for sampling by up to 1:1 nearest neighbour matching to adjust the numerical difference and balance the confounders between groups. The primary outcome was the live birth rate (LBR). Multivariable logistic analysis was used to evaluate the difference between these two protocols in relation to the LBR. RESULT(S): In this study, 1:1 propensity score matching was performed to create a perfect match of 964 patients in each group. After matching, the blastocyst formation rates, oestradiol (E2) value on Day hCG + 9, progesterone (P) value on Day hCG + 9, implantation rates, clinical pregnancy rates, and LBR were more favourable in the depot GnRH-a protocol than in the long GnRH-a protocol (P < 0.05). However, the moderate or severe OHSS rates were higher in the depot group than in the long group (P < 0.001). There were no significant differences in endometrial thickness, luteal support medication, early pregnancy loss rates, mid- and late-term pregnancy loss rates, or foetal malformation rates between the two protocols. CONCLUSION(S): Compared with the daily short-acting GnRH agonist protocol, the follicular-phase depot GnRH-a protocol might improve LBRs in normogonadotropic women without discernible differences in luteal function and child health.

Antioxidant and anti-tyrosinase activity of a novel stilbene analogue as an anti-browning agent.

BACKGROUND: Tyrosinase inhibitors find potential application in food, cosmetic and medicinal products, but most of the identified tyrosinase inhibitors are not suitable for practical use because of safety regulations or other problems. For the purpose of development of novel tyrosinase inhibitors that meet the requirement for practical application, a novel stilbene analogue (SA) was designed. RESULTS: SA was found to possess a potent inhibitory effect against both mono- and diphenolase activities of mushroom tyrosinase, with IC50 values of 1.56 and 7.15 µmol L-1 , respectively. Compared with a natural tyrosinase inhibitor - kojic acid - the anti-tyrosinase effect of SA was significantly improved. Analysis of inhibition kinetics indicated that SA was a reversible and competitive-noncompetitive mixed-type inhibitor. SA was also found to possess more potent antioxidant activities (DPPH, superoxide anion radical and hydroxyl radical scavenging ability) than those of kojic acid. Cell viability studies revealed that SA was non-toxic to two cell lines. Furthermore, an anti-browning test demonstrated that SA effectively delayed the blackening of shrimp. CONCLUSION: SA has potential as an anti-browning agent in foods. © 2021 Society of Chemical Industry.

Retinal Degeneration Caused by Ago2 Disruption.

Purpose: Argonaute proteins are key players in small RNA-guided gene silencing processes. Ago2 is the member of the Argonaute subfamily with slicer endonuclease activity and is critical for microRNA homeostasis and indispensable for biological development. However, the impact of Ago2 dysregulation in the retina remains to be fully explored. In this study, we studied the role of Ago2 in mouse retina. Methods: We explored the function of Ago2 in the mouse retina through an adeno-associated virus-mediated Ago2 disruption mouse model. An ERG was carried out to determine the retinal function. Spectral domain optical coherence tomography, fundus photographs, and immunostaining were performed to investigate the retinal structure. A quantitative RT-PCR assay was used to determine the expression of noncoding RNAs. Results: Both silencing and overexpression of Ago2 in mouse retina resulted in significant retinal morphological alterations and severe impairment of retinal function, mainly with a thinned outer nuclear layer, shortened inner segment/outer segment, and diminished ERG responses. Furthermore, Ago2 disruption resulted in alterations of noncoding RNAs in retina. Conclusions: Our finding demonstrated that Ago2 interruption led to severe retinal degeneration, suggested that Ago2 homeostasis contributed to retinal structural and functional maintenance.

Transplantation of GMP-grade human iPSC-derived retinal pigment epithelial cells in rodent model: the first pre-clinical study for safety and efficacy in China.

BACKGROUND: Age-related macular degeneration (AMD) is the leading cause of blindness in the elderly due in large part to age-dependent atrophy of retinal pigment epithelium (RPE) cells. RPE cells form a monolayer located between the choroid and the outer segments of photoreceptors, playing multifarious roles in maintenance of visual function. Allogeneically induced pluripotent stem cell-derived RPE (iPSC-RPE or iRPE) has become a potential approach for providing an abundant source of donors for clinical cell products. Transplantation of iRPE has been proven effective in rescuing impaired retinas in Royal College of Surgeons (RCS) rats after approximately 5 to 6 weeks. Here, we explore the long-term (19 weeks) safety and efficacy of human iRPE cell transplantation in pre-clinical animal models. METHODS: The expression of human RPE-specific markers in iRPE cells was determined using immunofluorescence staining. For the proliferative test, Ki-67 expression was also verified by immunofluorescence and flow cytometric analysis. Then, iRPE cells were transplanted into the subretinal space of immune-deficient NOD/SCID/IL-2Rgcnull (NSG) mice to assess their safety. To evaluate whether the transplanted cells could survive and rescue visual function, we performed color fundus photography, focal electroretinogram and immunostaining after delivering iRPE cells into the subretinal space of RCS rats. RESULTS: Human iRPE cells expressed native RPE-specific markers, such as microphthalmia-associated transcription factor (MiTF), retinal pigment epithelium-specific 65-kDa protein (RPE65) and tight-junction associated structural protein (ZO-1), and their proliferative capacity (Ki-67 expression) was poor after 25 days of induction. A tumorigenicity test revealed no tumor formation or abnormal proliferation in the immunodeficient mice after subretinal injection of 5×105 iRPE cells. The transplanted iRPE cells survived for at least 19 weeks and maintained visual function for 15 weeks. CONCLUSIONS: In the present study, we provided further evidence for the use of human iRPE transplantation to treat retinal degenerative disease in pre-clinical animal models. Therefore, we consider human iRPE cells a promising source of cell replacement therapy for AMD.

Design, synthesis and biological evaluation of potential anti-AD hybrids with monoamine oxidase B inhibitory and iron-chelating effects.

A series of active hybrids combining 3-hydroxypyridin-4(1H)-one and coumarin pharmacophores were designed and synthesized as potential agents for the treatment of Alzheimer's disease (AD). All the compounds exhibited excellent iron-chelating activities (pFe3+ = 14.8-19.2) and showed favorable monoamine oxidase B (MAO-B) inhibitory effects compared to the reference drug Pargyline (IC50 = 86.9 nM). Among them, compound 11 g displayed the best MAO-B inhibitory activity with an IC50 value of 99.3 nM. Molecular docking analysis showed that compound 11 g could enter the entrance cavity and substrate cavity of MAO-B. Furthermore, the compound 11 g had an excellent antioxidant effect and was capable of protecting from the amyloid-ß1-42 (Aß1-42) induced PC12 cell damage. In silico tools were applied for predicting the blood-brain barrier (BBB) penetration and compound 11 g was proved to overcome the brain exposure challenge. In the mice behavioral study, compound 11 g significantly ameliorated cognitive impairment induced by Scopolamine. More importantly, compound 11 g displayed favorable pharmacokinetic profiles in a rat model. In summary, compound 11 g, with both anti-MAO-B and iron-chelating ability, was proved to be a promising potential anti-AD agent for further optimization.

The road to restore vision with photoreceptor regeneration.

Neuroretinal diseases are the predominant cause of irreversible blindness worldwide, mainly due to photoreceptor loss. Currently, there are no radical treatments to fully reverse the degeneration or even stop the disease progression. Thus, it is urgent to develop new biological therapeutics for these diseases on the clinical side. Stem cell-based treatments have become a promising therapeutic for neuroretinal diseases through the replacement of damaged cells with photoreceptors and some allied cells. To date, considerable efforts have been made to regenerate the diseased retina based on stem cell technology. In this review, we overview the current status of stem cell-based treatments for photoreceptor regeneration, including the major cell sources derived from different stem cells in pre-clinical or clinical trial stages. Additionally, we discuss herein the major challenges ahead for and potential new strategy toward photoreceptor regeneration.

Human embryonic stem cell-derived organoid retinoblastoma reveals a cancerous origin.

Retinoblastoma (Rb) is the most prevalent intraocular malignancy in children, with a worldwide survival rate <30%. We have developed a cancerous model of Rb in retinal organoids derived from genetically engineered human embryonic stem cells (hESCs) with a biallelic mutagenesis of the RB1 gene. These organoid Rbs exhibit properties highly consistent with Rb tumorigenesis, transcriptome, and genome-wide methylation. Single-cell sequencing analysis suggests that Rb originated from ARR3-positive maturing cone precursors during development, which was further validated by immunostaining. Notably, we found that the PI3K-Akt pathway was aberrantly deregulated and its activator spleen tyrosine kinase (SYK) was significantly up-regulated. In addition, SYK inhibitors led to remarkable cell apoptosis in cancerous organoids. In conclusion, we have established an organoid Rb model derived from genetically engineered hESCs in a dish that has enabled us to trace the cell of origin and to test novel candidate therapeutic agents for human Rb, shedding light on the development and therapeutics of other malignancies.

Generation of Nonhuman Primate Model of Cone Dysfunction through In Situ AAV-Mediated CNGB3 Ablation.

A major challenge to the development of therapies for human retinal degenerative diseases is the lack of an ideal preclinical model because of the physiological differences between humans and most model animals. Despite the successful generation of a primate model through germline knockout of a disease-causing gene, the major issues restricting modeling in nonhuman primates (NHPs) are their relatively long lifespan, lengthy gestation, and dominant pattern of singleton births. Herein, we generated three cynomolgus macaques with macular in situ knockout by subretinal delivery of an adeno-associated virus (AAV)-mediated CRISPR-Cas9 system targeting CNGB3, the gene responsible for achromatopsia. The in vivo targeting efficiency of CRISPR-Cas9 was 12%-14%, as shown by both immunohistochemistry and single-cell transcriptomic analysis. Through clinical ophthalmic examinations, we observed a reduced response of electroretinogram in the central retina, which corresponds to a somatic disruption of CNGB3. In addition, we did not detect CRISPR-Cas9 residue in the heart, liver, spleen, kidney, brain, testis, or blood a year after administration. In conclusion, we successfully generated a NHP model of cone photoreceptor dysfunction in the central retina using an in situ CNGB3-knockout strategy.

Rational design, synthesis and biological evaluation of novel multitargeting anti-AD iron chelators with potent MAO-B inhibitory and antioxidant activity.

A series of (3-hydroxypyridin-4-one)-coumarin hybrids were developed and investigated as potential multitargeting candidates for the treatment of Alzheimer's disease (AD) through the incorporation of iron-chelating and monoamine oxidase B (MAO-B) inhibition. This combination endowed the hybrids with good capacity to inhibit MAO-B as well as excellent iron-chelating effects. The pFe3+ values of the compounds were ranging from 16.91 to 20.16, comparable to more potent than the reference drug deferiprone (DFP). Among them, compound 18d exhibited the most promising activity against MAO-B, with an IC50 value of 87.9 nM. Moreover, compound 18d exerted favorable antioxidant activity, significantly reversed the amyloid-ß1-42 (Aß1-42) induced PC12 cell damage. More importantly, 18d remarkably ameliorated the cognitive dysfunction in a scopolamine-induced mice AD model. In brief, a series of hybrids with potential anti-AD effect were successfully obtained, indicating that the design of iron chelators with MAO-B inhibitory and antioxidant activities is an attractive strategy against AD progression.

Ablation of Mature miR-183 Leads to Retinal Dysfunction in Mice.

Purpose: The microRNA cluster miR-183C, which includes miR-183 and two other genes, is critical for multiple sensory systems. In mouse retina, removal of this cluster results in photoreceptor defects in polarization, phototransduction, and outer segment elongation. However, the individual roles of the three components of this cluster are not clearly known. We studied the separate role of mouse miR-183 in in vivo. Methods: miR-183 knockout mice were generated using the CRISPR/Cas9 genome-editing system. Electroretinography were carried out to investigate the changes of retinal structures and function. miR-183 was overexpressed by subretinal adeno-associated virus (AAV) injection in vivo. Rnf217, a target of miR-183 was overexpressed by cell transfection of the photoreceptor-derived cell line 661W in vitro. RNA sequencing and quantitative real-time polymerase chain reaction (qRT-PCR) were performed to compare the gene expression changes in AAV-injected mice and transfected cells. Results: The miR-183 knockout mice showed progressively attenuated electroretinogram responses. Over- or under-expression of Rnf217, a direct target of miR-183, misregulated expression of cilia-related BBSome genes. Rnf217 overexpression also led to compromised electroretinography responses in WT mice, indicating that it may contribute to functional abnormalities in miR-183 knockout mice. Conclusions: miR-183 is essential for mouse retinal function mediated directly and indirectly through Rnf217 and cilia-related genes. Our findings provide valuable insights into the explanation and analysis of the regulatory role of the individual miR-183 in miR-183C.