2.α/Sulfono-γ-AA peptide hybrids agonist of GLP-1R with prolonged action both in vitro and in vivo.
Yan SHI ; Candy LEE ; Peng SANG ; Zaid AMSO ; David HUANG ; Weixia ZHONG ; Meng GU ; Lulu WEI ; Vân T B NGUYEN-TRAN ; Jingyao ZHANG ; Weijun SHEN ; Jianfeng CAI
Acta Pharmaceutica Sinica B 2023;13(4):1648-1659
Peptides are increasingly important resources for biological and therapeutic development, however, their intrinsic susceptibility to proteolytic degradation represents a big hurdle. As a natural agonist for GLP-1R, glucagon-like peptide 1 (GLP-1) is of significant clinical interest for the treatment of type-2 diabetes mellitus, but its in vivo instability and short half-life have largely prevented its therapeutic application. Here, we describe the rational design of a series of α/sulfono-γ-AA peptide hybrid analogues of GLP-1 as the GLP-1R agonists. Certain GLP-1 hybrid analogues exhibited enhanced stability (t 1/2 > 14 days) compared to t 1/2 (<1 day) of GLP-1 in the blood plasma and in vivo. These newly developed peptide hybrids may be viable alternative of semaglutide for type-2 diabetes treatment. Additionally, our findings suggest that sulfono-γ-AA residues could be adopted to substitute canonical amino acids residues to improve the pharmacological activity of peptide-based drugs.
3.Variation of sexual dimorphism and asymmetry in disease expression of inflammatory arthritis among laboratory mouse models with different genomic backgrounds
Wei DONG ; Cheng TIAN ; Z. Galvin LI ; David BRAND ; Yanhong CAO ; Xiaoyun LIU ; Jiamin MA ; Andy CHAI ; Linda K. MYERS ; Jian YAN ; Karen HASTY ; John STUART ; Yan JIAO ; Weikuan GU ; Xiaojun CAI
Laboratory Animal Research 2023;39(4):402-410
Sex difference has shown in the arthritis diseases in human population and animal models. We investigate how the sex and symmetry vary among mouse models with different genomic backgrounds. Disease data of sex and limbs accumulated in the past more than two decades from four unique populations of murine arthritis models were analyzed. They are (1) interleukin-1 receptor antagonist (IL-1ra) deficient mice under Balb/c background (Balb/c KO); (2) Mice with collagen II induced arthritis under DBA/1 background; (3) Mice with collagen II induced arthritis under C57BL/6 (B6) background and (4) A F2 generation population created by Balb/c KO X DBA/1 KO.Our data shows that there is a great variation in sexual dimorphism for arthritis incidence and severity of arthritis in mice harboring specific genetic modifications. For a F2 population, the incidence of arthritis was 57.1% in female mice and 75.6% in male mice. There was a difference in severity related to sex in two populations: B6.DR1/ B6.DR4 (P < 0.001) and F2 (P = 0.023) There was no difference Balb/c parental strain or in collagen-induced arthritis (CIA) in DBA/1 mice. Among these populations, the right hindlimbs are significantly higher than the scores for the left hindlimbs in males (P < 0.05). However, when examining disease expression using the collagen induced arthritis model with DBA/1 mice, sex-dimorphism did not reach statistical significance, while left hindlimbs showed a tendency toward greater disease expression over the right. Sexual dimorphism in disease expression in mouse models is strain and genomic background dependent. It sets an alarm that potential variation in sexual dimorphism among different racial and ethnic groups in human populations may exist. It is important to not only include both sexes and but also pay attention to possible variations caused by disease expression and response to treatment in all the studies of arthritis in animal models and human populations.
4.2-Hexyl-4-Pentylenic Acid (HPTA) Stimulates the Radiotherapy-induced Abscopal Effect on Distal Tumor through Polarization of Tumor-associated Macrophages.
Wen Hua DUAN ; Li Ya JIN ; Zu Chao CAI ; David LIM ; Zhi Hui FENG
Biomedical and Environmental Sciences 2021;34(9):693-704
Objective:
The aim of this study was to explore the effects of 2-hexyl-4-pentylenic acid (HPTA) in combination with radiotherapy (RT) on distant unirradiated breast tumors.
Methods:
Using a rat model of chemical carcinogen (7,12-dimethylbenz[a]anthracene,DMBA)-induced breast cancer, tumor volume was monitored and treatment response was evaluated by performing HE staining, immunohistochemistry, immunofluorescence, qRT-PCR, and western blot analyses.
Results:
The results demonstrated that HPTA in combination with RT significantly delayed the growth of distant, unirradiated breast tumors. The mechanism of action included tumor-associated macrophage (TAM) infiltration into distant tumor tissues, M1 polarization, and inhibition of tumor angiogenesis by IFN-γ.
Conclusion
The results suggest that the combination of HPTA with RT has an abscopal effect on distant tumors
Animals
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Antineoplastic Agents/therapeutic use*
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Cell Proliferation/radiation effects*
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Combined Modality Therapy
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Cytokines/immunology*
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Fatty Acids, Unsaturated/therapeutic use*
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Female
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Mammary Neoplasms, Experimental/radiotherapy*
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Rats
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Tumor-Associated Macrophages/radiation effects*
5.hCD47 induces immune tolerance of human macrophages to porcine endothelial cells
Wenbao HU ; Dengke PAN ; David K.C.Cooper ; Zhiming CAI ; Lisha MOU
Organ Transplantation 2019;10(2):165-
Objective To investigate the effect of human CD47 (hCD47) in inducing the immune tolerance of human macrophages to porcine endothelial cells. Methods The porcine iliac endothelial cell (PIEC) transfected with pCDH-hCD47-FLAG plasmid was assigned into the pCDH-hCD47 group, PIEC transfected with pCDH-FLAG empty vector plasmid was assigned into the pCDH group, PIEC transfected with hCD47-dN was assigned into the pCDH-hCD47-dN group and human umbilical vein endothelial cell (HUVEC) was assigned into the positive control group. The cells were co-cultured with human macrophages to detect and analyze the phosphorylation of signal regulatory protein α (SIRPα) and the killing effect of human macrophages on PIEC. Furthermore, porcine arteriae endothelial cell (PAEC) was isolated from GT-/- and GT-/-/ hCD 47 gene editing pigs to analyze the phosphorylation of SIRPα and the killing effect of human macrophages on PAEC. Results The pCDH group cells could not induce the phosphorylation of SIRPα, whereas the pCDH-hCD47 group cells could activate the phosphorylation of SIRPα after 10 min co-culture with human macrophages, and the degree of phosphorylation of SIRPα was increased with the prolongation of the co-culture time. The pCDH-hCD47-dN group cells failed to activate the phosphorylation of SIRPα. Human macrophages exerted significant effect on killing the pCDH group cells. The pCDH-hCD47 group cells could evidently inhibit the killing effect of human macrophages (
7.Glucagon-like peptide 1 improves learning and memory abilities of rats with type 2 diabetes.
Zhao-Guang TAN ; ; Wei-Hong GAO ; Xiang-Sheng CAI ; Fang WANG ; Hong-Xiang HUI
Journal of Southern Medical University 2016;36(10):1345-1351
OBJECTIVETo investigate the effect of glucagon-like peptide 1 (GLP-1) on cognitive dysfunction in diabetic rats.
METHODSMale SD rats were randomly divided into normal control group, diabetes mellitus (DM) group, and GLP-1 treatment group. Rat models of type 2 diabetes were established by high-sugar and high-fat feeding and streptozotocin (STZ) injection, and 25 days after the onset of diabetes, GLP-1 was infused in GLP-1 treatment group at the rate of 30 pmol·kg·minvia a subcutaneous osmotic pump for 7 days. The learning and cognitive ability of the rats was assessed with Morris water maze test, and the expression of cognition-related genes in the hippocampus tissue was detected with real-time PCR, Western blotting and immunohistochemical staining.
RESULTSCompared with the normal control group, the diabetic rats showed significantly decreased learning and memory abilities (P<0.05) with increased hippocampal expressions of APP, BACE1, Arc, ERK1/2, PKA, and PKC mRNAs (P<0.05) and Arc protein. Compared with diabetic rats, GLP-1-treated rats showed significantly improvements in the learning and memory function (P<0.05) with decreased expressions of APP, BACE1, Arc, ERK1/2, and PKA mRNAs (P<0.05) and Arc protein.
CONCLUSIONGLP-1 can improve cognitive dysfunctions in diabetic rats possibly by regulating the PKC, PKA, and ERK1/2 pathways and inhibiting Arc expression in the hippocampus.
Animals ; Diabetes Mellitus, Experimental ; drug therapy ; Diabetes Mellitus, Type 2 ; drug therapy ; Glucagon-Like Peptide 1 ; pharmacology ; Hippocampus ; drug effects ; Learning ; drug effects ; Male ; Memory ; drug effects ; Rats ; Rats, Sprague-Dawley ; Real-Time Polymerase Chain Reaction ; Streptozocin
8.Species Diversity and Seasonal Distribution of Culicoides spp. (Diptera: Ceratopogonidae) in Jeju-do, Republic of Korea.
Heung Chul KIM ; Glenn A BELLIS ; Myung Soon KIM ; Terry A KLEIN ; David GOPURENKO ; Du Cheng CAI ; Hyun Ji SEO ; In Soo CHO ; Jee Yong PARK
The Korean Journal of Parasitology 2015;53(4):501-506
Biting midges belonging to the genus Culicoides (Diptera: Ceratopogonidae) were collected by Mosquito Magnet(R) and black light traps at 5 sites on Jeju-do, Republic of Korea (Korea), from May-November 2013 to determine species diversity and seasonal distribution. A total of 4,267 specimens were collected, of which 99.9% were female. The most common species was Culicoides tainanus (91.8%), followed by C. lungchiensis (7.2%) and C. punctatus (0.6%), while the remaining 4 species accounted for <0.5% of all Culicoides spp. that were collected. High numbers of C. tainanus were collected in May, followed by decreasing numbers through August, and then increasing numbers through November when surveillance was terminated. Peak numbers of C. lungchiensis were collected during September, with low numbers collected from May-August and October-November. The presence of C. lungchiensis in Korea was confirmed by morphological and molecular analyses.
Animals
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*Biodiversity
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Ceratopogonidae/classification/*growth & development
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Female
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Insect Vectors/classification/*growth & development
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Male
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Phylogeny
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Republic of Korea
;
Seasons
9.Comparison of ocular modulation transfer function determined by a ray-tracing aberrometer and a double-pass system in early cataract patients.
Liya QIAO ; Xiuhua WAN ; Xiaogu CAI ; Balamurali VASUDEVAN ; Ying XIONG ; Jiaxuan TAN ; Zheng GUAN ; David A ATCHISON ; Ningli WANG ;
Chinese Medical Journal 2014;127(19):3454-3458
BACKGROUNDThe evaluation of retinal image quality in cataract eyes has gained importance and the clinical modulation transfer functions (MTF) can obtained by aberrometer and double pass (DP) system. This study aimed to compare MTF derived from a ray tracing aberrometer and a DP system in early cataractous and normal eyes.
METHODSThere were 128 subjects with 61 control eyes and 67 eyes with early cataract defined according to the Lens Opacities Classification System III. A laser ray-tracing wavefront aberrometer (iTrace) and a double pass (DP) system (OQAS) assessed ocular MTF for 6.0 mm pupil diameters following dilation. Areas under the MTF (AUMTF) and their correlations were analyzed. Stepwise multiple regression analysis assessed factors affecting the differences between iTrace- and OQAS-derived AUMTF for the early cataract group.
RESULTSFor both early cataract and control groups, iTrace-derived MTFs were higher than OQAS-derived MTFs across a range of spatial frequencies (P < 0.01). No significant difference between the two groups occurred for iTrace-derived AUMTF, but the early cataract group had significantly smaller OQAS-derived AUMTF than did the control group (P < 0.01). AUMTF determined from both the techniques demonstrated significant correlations with nuclear opacities, higher-order aberrations (HOAs), visual acuity, and contrast sensitivity functions, while the OQAS-derived AUMTF also demonstrated significant correlations with age and cortical opacity grade. The factors significantly affecting the difference between iTrace and OQAS AUMTF were root-mean-squared HOAs (standardized beta coefficient = -0.63, P < 0.01) and age (standardized beta coefficient = 0.26, P < 0.01).
CONCLUSIONSMTFs determined from a iTrace and a DP system (OQAS) differ significantly in early cataractous and normal subjects. Correlations with visual performance were higher for the DP system. OQAS-derived MTF may be useful as an indicator of visual performance in early cataract eyes.
Aberrometry ; methods ; Adult ; Aged ; Cataract ; physiopathology ; Female ; Humans ; Male ; Middle Aged ; Visual Acuity ; physiology
10.Statistical physics approaches to neuronal network dynamics.
Acta Physiologica Sinica 2011;63(5):453-462
We review a statistical physics approach for reduced descriptions of neuronal network dynamics. From a network of all-to-all coupled, excitatory integrate-and-fire neurons, we derive a (2+1)-D advection-diffusion equation for a probability distribution function, which describes neuronal population dynamics. We further show how to derive a (1+1)-D kinetic equation, using a moment closure scheme, without introducing any new parameters to the system. We demonstrate the numerical accuracy of our kinetic theory by comparing its results to Monte Carlo simulations of the full integrate-and-fire neuronal network.
Animals
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Computer Simulation
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Humans
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Models, Neurological
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Monte Carlo Method
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Nerve Net
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physiology
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Neural Networks (Computer)
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Neurons
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physiology

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