Genipin relieves diabetic retinopathy by down-regulation of advanced glycation end products via the mitochondrial metabolism related signaling pathway

BACKGROUND Glycation is an important step in aging and oxidative stress,which can lead to endothelial dysfunction and cause severe damage to the eyes or kidneys of diabetics.Inhibition of the formation of advanced glycation end products(AGEs)and their cell toxicity can be a useful therapeutic strategy in the prevention of diabetic retinopathy(DR).Gardenia jasminoides Ellis(GJE)fruit is a selective inhibitor of AGEs.Genipin is an active compound of GJE fruit,which can be employed to treat diabetes.AIM To confirm the effect of genipin,a vital component of GJE fruit,in preventing human retinal microvascular endothelial cells(hRMECs)from AGEs damage in DR,to investigate the effect of genipin in the down-regulation of AGEs expression,and to explore the role of the CHGA/UCP2/glucose transporter 1(GLUT1)signal pathway in this process.METHODS In vitro,cell viability was tested to determine the effects of different doses of glucose and genipin in hRMECs.Cell Counting Kit-8(CCK-8),colony formation assay,flow cytometry,immunofluorescence,wound healing assay,transwell assay,and tube-forming assay were used to detect the effect of genipin on hRMECs cultured in high glucose conditions.In vivo,streptozotocin(STZ)induced mice were used,and genipin was administered by intraocular injection(IOI).To explore the effect and mechanism of genipin in diabetic-induced retinal dysfunction,reactive oxygen species(ROS),mitochondrial membrane potential(MMP),and 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-d-glucose(2-NBDG)assays were performed to explore energy metabolism and oxidative stress damage in high glucose-induced hRMECs and STZ mouse retinas.Immunofluorescence and Western blot were used to investigate the expression of inflammatory cytokines[vascular endothelial growth factor(VEGF),SCG3,tumor necrosis factor-alpha(TNF-α),interleukin(IL)-1β,IL-18,and nucleotide-binding domain,leucine-rich-containing family,pyrin domain-containing 3(NLRP3)].The protein expression of the receptor of AGEs(RAGE)and the mitochondria-related signal molecules CHGA,GLUT1,and UCP2 in high glucose-induced hRMECs and STZ mouse retinas were measured and compared with the genipin-treated group.RESULTS The results of CCK-8 and colony formation assay showed that genipin promoted cell viability in high glucose(30 mmol/L D-Glucose)-induced hRMECs,especially at a 0.4μmol/L dose for 7 d.Flow cytometry results showed that high glucose can increase apoptosis rate by 30%,and genipin alleviated cell apoptosis in AGEs-induced hRMECs.A high glucose environment promoted ATP,ROS,MMP,and 2-NBDG levels,while genipin inhibited these phenotypic abnormalities in AGEs-induced hRMECs.Furthermore,genipin remarkably reduced the levels of the pro-inflammatory cytokines TNF-α,IL-1β,IL-18,and NLRP3 and impeded the expression of VEGF and SCG3 in AGEs-damaged hRMECs.These results showed that genipin can reverse high glucose induced damage with regard to cell proliferation and apoptosis in vitro,while reducing energy metabolism,oxidative stress,and inflammatory injury caused by high glucose.In addition,ROS levels and glucose uptake levels were higher in the retina from the untreated eye than in the genipin-treated eye of STZ mice.The expression of inflammatory cytokines and pathway protein in the untreated eye compared with the genipin-treated eye was significantly increased,as measured by Western blot.These results showed that IOI of genipin reduced the expression of CHGA,UCP2,and GLUT1,maintained the retinal structure,and decreased ROS,glucose uptake,and inflammation levels in vivo.In addition,we found that SCG3 expression might have a higher sensitivity in DR than VEGF as a diagnostic marker at the protein level.CONCLUSION Our study suggested that genipin ameliorates AGEs-induced hRMECs proliferation,apoptosis,energy metabolism,oxidative stress,and inflammatory injury,partially via the CHGA/UCP2/GLUT1 pathway.Control of advanced glycation by IOI of genipin may represent a strategy to prevent severe retinopathy and vision loss.

Genipin对糖尿病小鼠下丘脑细胞凋亡指数及解偶联蛋白2表达的影响

目的探讨genipin对糖尿病小鼠下丘脑细胞凋亡指数(AI)及解偶联蛋白2(UCP2)表达的影响。方法 48只健康雄性小鼠随机分为正常对照组、糖尿病模型组和genipin低、高剂量干预组,每组12只小鼠。采用长期高脂饮食及链脲佐菌素胰岛破坏法建立2型糖尿病小鼠模型。Genipin低、高剂量干预组小鼠分别给予5 mg/(kg.d)、10 mg/(kg.d)的genipin 0.1 ml连续灌胃2周,正常对照组和糖尿病模型组用等量生理盐水替代。分别采用TUNEL染色法和免疫组化染色检测并计算各组小鼠下丘脑AI和UCP2蛋白阳性细胞率;采用实时PCR和Western Blot法检测下丘脑UCP2 mRNA和蛋白的表达水平。结果糖尿病模型组、genipin低剂量和高剂量干预组下丘脑AI明显高于正常对照组(均P<0.05);而genipin低剂量和高剂量干预组下丘脑AI明显低于糖尿病模型组(均P<0.05);且genipin低剂量干预组和genipin高剂量干预组间差异无统计学意义。糖尿病模型组UCP2蛋白阳性细胞率明显高于正常对照组(P<0.05),而genipin低剂量和高剂量干预组UCP2蛋白阳性细胞率均明显低于糖尿病模型组(均P<0.05)。Genipin低剂量和高剂量干预组UCP2 mRNA和蛋白的表达水平均明显低于糖尿病模型组(均P<0.05)。与genipin低剂量干预组比较,geni-pin高剂量干预组UCP2蛋白阳性细胞率、UCP2 mRNA和蛋白的表达水平明显降低(均P<0.05)。结论 Ge-nipin可以减少糖尿病小鼠下丘脑细胞凋亡和UCP2的表达。

Correlation of discoloration and biomechanical properties in porcine sclera induced by genipin

·AIM: To study the feasibility of using the discoloration to evaluate the biomechanical properties after treating with genipin.·METHODS: Porcine cadaver eyes were treated for30 min with 1.0%(by w/v) genipin. Untreated samples were used as controls. After treatment, scleral strips of4.0 ×10.0-mm2 were cut. The denaturation temperature(Td) measurement and stress-strain test were performed after taking photograph to analyze the color.·RESULTS: Within 24 h after treating with genipin, the sclera exhibited a bluish color which became deeper with time. And the denaturation temperature also was increased gradually. Compared with untreated groups, at1, 6, 12, 24 and 36 h after treatment, the ultimate stress were increased by 56%, 153%, 173%, 225% and 211%respectively. The Young’s modulus at 10% strain also increased by 170%, 246%, 264%, 389% and 288%respectively. There were strong correlation between the discoloration and the biomechanical properties(ΔE-Ultimate stress:R2=0.892, P =0.00; ΔE-Young’s modulus:R2=0.602, P =0.00).·CONCLUSION: Genipin could be used to strengthen collagen gradually in a relatively short time span. And the biomechanical properties could be reliably evaluated via simple visible discoloration.

Biomechanics of sclera crosslinked using genipin in rabbit

AIM：To strengthen the biomechanics of collagen by crosslinking rabbit scleral collagen with genipin to develop a new therapy for preventing myopic progression. METHODS：Ten New Zealand rabbits were treated with 0.5 mmol/L genipin injected into the sub-Tenon＇s capsule in the right eyes. Untreated contralateral eyes served as the control. The treated area was cut into scleral strips measuring 4.0 mm×10.0 mm for stress-strain measurements（n=5）. The remaining five treated eyes were prepared for histological examination.RESULTS：Compared to the untreated scleral strips,the genipin-crosslinked scleral strips showed that the ultimate stress and Young＇s modulus at 10% strain were increased by the amplitude of 130% and 303% respectively,ultimate strain was decreased by 24%. There had no α-smooth muscle actin（α-SMA）positive cells in control and treated sclera. Histologically,there was no sign of apoptosis in the sclera,choroid,and retina; and no side effects were found in the peripheral cornea and optic nerve adjacent to the treatment area.CONCLUSION：Genipin induced crosslinking of collagen can increase its biomechanical behavior by direct strengthening of the extracellular matrix in rabbit sclera,with no α-SMA expression seen in the myofibroblasts. As there is no evidence of cytotoxicity in the scleral,choroidal,and retinal cells,genipin is likely a promising agent to strengthen the weakened sclera to prevent myopic progression.

Antimicrobial Activity of Minocycline-Loaded Genipin-Crosslinked Nano-Fibrous Chitosan Mats for Guided Tissue Regeneration

Antimicrobial delivery has been advocated for guided tissue regeneration (GTR) or guided bone regeneration (GBR) therapies involving patients with aggressive or unresolved periodontitis/peri-implantitis. Electrospun chitosan membranes demonstrate several advantages over traditional GTR barrier membranes because they stimulate healing, mimic the topology of the extracellular matrix, and allow for diffusion of nutrients and wastes into/out of the graft site, and were shown to stimulate bone formation in a rabbit calvarial criticalsize defect model. Previously, we have shown improvements in mechanical properties and degradation kinetics by crosslinking electrospun membranes with 5 mM or 10 mM genipin. We have also demonstrated the ability of elecrospun chitosan membranes to inhibit lippopolysaccharide (LPS)-induced monocyte activation. In this study, minocycline was incorporated into the chitosan membrane by passive absorption at 5 or 10 mg/mL. The minocycline-loaded membranes and control membranes (carrier only) were tested against Porphyromonas gingivalis (P. gingivalis) by repeated zone of inhibition (ZOI) measurements. Testing showed that uncrosslinked and genipin-crosslinked membranes have similar capacity to absorb aqueous solutions (swelling ratio 1.7 - 2.2). Minocycline loading resulted in bacterial inhibition for up to 8 days from crosslinked membranes (with 11 mm initial ZOI) whereas uncrosslinked membranes loaded with minocycline only inhibited bacteria for 4 days (with 8 mm initial ZOI). These in vitro results suggest that genipin-crosslinked electrospun chitosan membranes loaded with minocycline may be able to reduce early bacterial contamination of GTR graft sites.

Preparation and characterization of genipin-cross-linked chitosan microparticles by water-in-oil emulsion solvent diffusion method

Chitosan (CS) microparticles with and without cross-linking were prepared by a water-in-oil emulsion solvent diffusion method without any surfactants. Aqueous CS solution and ethyl ace- tate were used as water and oil phases, respectively. Genipin was used as a cross-linker. Influ- ences of genipin ratios and cross-linking times on CS microparticle characteristics were investigated. Non-cross-linked and cross-linked CS microparticles were spherical in shape and rough in surface. Microparticle matrices showed porous structures. Surface roughness, mean par- ticle sizes and bulk density of CS microparticles increased and their dissolutions in acetic acid solution decreased when genipin ratio and cross- linking time increased.

Genipin Cross-Linked Polyvinyl Alcohol-Gelatin Hydrogel for Bone Regeneration

Polyvinyl alcohol gelatin hydrogels were fabricated using genipin as a crosslinking agent for bone regeneration application. Optimized formulation of PVA-GE hydrogel was fabricated using genipin as crosslinking agent. Characterizations such as FTIR, morphology, porosity, pore size, degradation and swelling rate were investigated. Bone regeneration potential of optimized genipin cross-linked polyvinyl alcohol-gelatin (PVA20) hydrogels was assessed by implanting in rabbit’s femur defect for 1, 5 and 15 weeks period. Results showed interconnected porosity as observed in scanning electron microscopy and successful crosslinking as confirmed by FTIR analysis. Increased porosity (92% ± 2.46%) and pore size distribution (100 - 200 μm) were also observed as well as decrease in swelling rate (426% ± 10.50%). Bone formation was evident in micro-CT after 5 and 15 days of in vivo implantation period. Micro-CT analysis showed 32.67% increased bone formation of PVA-GE hydrogel defect compared with negative control after 15 weeks of in-vivo implantation. Histological analyses showed no inflammatory reaction post implantation and increase in cell matrix formation after 5 and 15 weeks. The combined physical and chemical method of crosslinking promises improved mechanical properties of PVA-GE hydrogel making it a potential scaffold for bone tissue engineering applications.

Development of genipin crosslinked gelatin matrices on surface interaction: Enhancing the biocompatibility by attenuating sterile inflammation

The inflammation can be stimulated by the surgical implantation and biomaterial presence through the foreign body via bio-interface.Macrophages play a key role in the interaction of host tissue to implant surfaces.In present study,the immuno-inflammatory responses of genipin crosslinked gelatin matrices(GCGM)to macrophages in vitro and the host tissue surfaces in rats were investigated.The results showed that the mechanical properties,swelling and degradation of gelatin matrices were improved by the crosslinking of genipin at physiological conditions.The macrophage on the surface of GCGM could avoid to be activated.The interaction of macrophage and GCGM suggested that GCGM could reduce the inflammatory response with downregulating the production and m RNA expression of pro-inflammatory cytokines.The anti-inflammatory effect of GCGM was demonstrated to be related to inhibit nuclear factor kappa-B(NF-κB)signaling pathway.Furthermore,gelatin matrices crosslinked with genipin could decrease the acute and chronic inflammatory response interacting with host tissue surfaces to enhance the biocompatibility in rats.These results showed that GCGM could avoid to active macrophages and were endowed with anti-inflammatory properties,suggesting the significant potential for clinical success with the development of immunomodulatory biomaterials.

The Cytocompatibility of Genipin-Crosslinked Silk Fibroin Films

There is an increasing demand for crosslinking methods of silk fibroin (SF) scaffolds in biomedical applications that could maintain the biocompatibility, bioactivity as well as improve the water resistance and mechanical properties of SF materials. In this study, SF was crosslinked effectively with genipin which is a naturally occurring iridoid glucoside and the crosslinking mechanism was investigated through FTIR and amino acid analysis. The results showed that genipin could react with the -NH2 groups on the side chains of SF macromolecules and to form inter- and intra-molecular covalent bonds, and improved the stability of SF materials significantly. In vitro, the performances of genipin-crosslinked SF films were assessed by seeding L929 cells and compared with ethanol-processed SF films, glutaraldehyde and polyethylene glycol diglycidyl ether crosslinked ones. The genipin-crosslinked SF films showed a similar affinity to cells as ethanol-processed ones, and a higher bioactivity in promoting cell growth and proliferation, inhibition of cell apoptosis, and maintenance of normal cell cycle compared with glutaraldehyde and polyethylene glycol diglycidyl ether crosslinked SF films. These features, combined with the decrease of brittleness of SF films crosslinked with chemical methods, substantiated genipin as an effective and biocompatible agent for the manufacturing of bioactive SF materials which used as tissue engineering scaffolds and drug delivery carriers.

Study on Characteristics of Acellular Bovine Pericardium Crosslinked with Genipin

The study used a naturally occurring crosslinking reagent-genipin to chemically modify acellular bovine pericardium, prepare cardiac valve tissue engineering scaffold material,and evaluated genipin crosslinked acellular matrix of bovine pericardium by investigating the physical and chemical properties of the tissues, such as the surface properties, crosslinking characteristics, mechanical properties, resistance to enzymatic capacity in vitro, and hemolysis tests. The results showed that acellular bovine pericardium matrix erosslinked with genipin was strong hydrophilicity, high crosslinking index, and stable structure, which can maintain good mechanical properties. As a kind of scaffold material for valve tissue engineering, it has wide application prospect.

A temperature-regulated bioorthogonal reaction to target lysine:Hemiacetal pharmacophore in genipin irreversibly binds with UCP2,inhibiting mitochondrial thermogenesis

Mitochondria are essential for eukaryotic life as powerhouses for energy metabolism. Excessive mitochondrial hyperthermia and reactive oxygen species(ROS) production have been associated with aging, cancer,neurodegenerative diseases, and other disorders. Uncoupling protein 2(UCP2) is the effector responsible for regulating cellular thermogenesis and ROS production via dissipating protons in an electrochemical gradient. A UCP2 inhibitor named genipin(GNP) is being researched for its effect on mitochondrial temperature, but little is known about its mechanisms. This study developed several molecular probes to explore the interactions between GNP and UCP2. The result indicated that the hemiacetal structure in GNP could selectively react with the ?-amine of lysine on the UCP2 proton leakage channel through ringopening condensation at the mitochondrial, cellular, and animal levels. A notable feature of the reaction is its temperature sensitivity and ability to conjugate with UCP2 at high fever as lysine-specific covalent inhibitors that prevent mitochondrial thermogenesis. The result not only clarifies the existence of an antipyretic properties of GNP via its irreversible coupling to UCP2, but also reveals a bioorthogonal reaction of hemiacetal iridoid aglycone for selectively binding with the ?-amine of lysine on proteins.

Genipin交联明胶/溶菌酶缓释抗菌膜材料的微结构与性能研究

针对亲水明胶膜材料对抗菌剂缓释能力较差的问题,采用生物交联剂(genipin)调节膜材料微结构,制备出新型控释明胶/溶菌酶复合膜材料。系统研究了复合膜材料的力学性能、水汽阻隔性能、膨胀性和热性质等物理性能,并用AFM研究了膜材料的表面微结构,探讨了其结构-性能之间的关系。结果表明:genipin交联显著改善复合膜材料的力学性能,TS值从9.72 MPa逐渐增加至18.80 MPa;复合膜材料的膨胀度(swelling)随genipin浓度增加急剧下降,从1316%降至~200%;genipin交联提升复合膜材料的热稳定性。复合膜材的表面粗糙度依赖于genipin浓度,在低浓度段(0~1.0%),膜材料呈现平整表面微结构;高浓度(2.0%)时,膜表面出现不规则的突起,变得粗糙。适度的genipin交联有助于形成有序的三维网络结构,改善复合膜材料的物理性能;高浓度的genipin过度交联明胶基质,形成团聚状聚集物,及弱化明胶分子间相互作用,进而弱化膜材料的水汽阻隔能力。

基于京尼平结构的衍生物设计与合成及其对HepG2细胞毒性的研究

目的:设计并合成一系列基于京尼平结构的环烯醚萜类衍生物,并探讨其对HepG2细胞的毒性作用,为寻找具有肝保护作用的药物提供一定的理论指导。方法:以京尼平为起始物,以三氟化硼乙醚为催化剂,在低温无水无氧体系下与低碳醇(甲醇、乙醇、正丙醇、异丙醇、正丁醇、叔丁醇)进行S_(N)1取代反应,获得的产物经^(1)H-NMR进行结构表征;采用CCK-8法评价化合物对HepG2细胞的细胞毒性,并以谷胱甘肽为阳性对照,以IC_(50)值表示其毒性强弱。结果:设计并合成了6个京尼平衍生物,分别是1-O-甲基京尼平、1-O-乙基京尼平、1-O-正丙基京尼平、1-O-异丙基京尼平、1-O-正丁基京尼平、1-O-叔丁基京尼平,经^(1)H-NMR表征其结构正确。细胞实验显示,谷胱甘肽的IC_(50)值>1 000μmol/L,京尼平的IC_(50)值为(558.70±22.81)μmol/L,1-O-正丙基京尼平、1-O-正丁基京尼平的IC_(50)值分别为(537.40±188.10)μmol/L、(586.10±42.41)μmol/L,细胞毒性均低于谷胱甘肽,但与京尼平相近;1-O-异丙基京尼平的IC_(50)值为(628.30±38.72)μmol/L,低于谷胱甘肽,但高于京尼平;1-O-甲基京尼平、1-O-乙基京尼平、1-O-叔丁基京尼平的IC_(50)值分别为(324.30±55.67)μmol/L、(111.95±18.06)μmol/L、(91.10±15.20)μmol/L,均低于谷胱甘肽和京尼平。结论:合成了6个京尼平衍生物,获得了一条简单的、可控的京尼平衍生物的合成方法;其中京尼平衍生物1-O-正丙基京尼平、1-O-异丙基京尼平、1-O-正丁基京尼平对HepG2细胞毒性较小。

Potential prospects of Chinese medicine application in diabetic retinopathy

Current treatment strategies for diabetic retinopathy(DR),an eye condition that can lead to blindness,have mainly focused on proliferative DR,including vitreous injection,retinal photocoagulation,and vitrectomy.Vitreous injections mainly depend on anti-vascular endothelial growth factor therapy.In this editorial,we comment on the article by Sun et al.We focus specifically on the mechanisms of the protective effect of genipin on the retina.Genipin is a gardenia extract used in traditional Chinese medicine(TCM).In their study,the authors suggest that controlling advanced glycosylation by the intraocular injection of genipin may be a strategy for preventing retinopathy.The innovative use of a Chinese medicine extract injected into the eye to achieve a curative effect has attracted our attention.Although TCM is effective in treating DR,the topical application of DR,especially intraocular injections,is not yet feasible.Herein,we present a brief analysis of effective Chinese medicines for the treatment of DR.The effectiveness of local injections of TCM applied directly into the eyes holds promise as an effective treatment approach for DR.

Genipin交联丝素蛋白纳米纤维膜的制备与性能

利用Genipin对再生丝素蛋白进行交联改性,并通过静电纺丝法制备交联的丝素蛋白纳米纤维膜。利用场发射扫描电镜、红外光谱仪、X射线衍射仪、热重分析仪以及拉力机等对其结构与性能进行表征与测试。结果表明,随着交联剂Genipin质量比的增加,交联度增加,静电纺丝素蛋白纳米纤维平均直径增大,标准偏差增大;Genipin交联对丝素蛋白纳米纤维结晶结构影响不大,但热性能提高;常温条件下,随着Genipin质量比从2%提高至15%,丝素蛋白纳米纤维膜的力学性能逐渐增强,质量比为10%时,其力学性能较好,拉伸强度和断裂应变分别为19.6MPa和5.9%;随着试验温度从40℃升高到200℃,丝素蛋白纳米纤维膜的拉伸强度和断裂应变先增大然后减小,当试验温度为80℃时,其力学性能较好,拉伸强度和断裂应变分别为41.6MPa和8.6%。

京尼平对下咽癌FaDu细胞增殖及线粒体功能的影响

目的:探讨解偶联蛋白2(UCP2)抑制剂京尼平(GEN)对人下咽癌FaDu细胞增殖及线粒体功能的影响。方法:使用不同浓度的GEN作用于FaDu细胞24 h,实验分为GEN 0(对照)、50、100、200和400μmol/L组。采用CCK-8法检测各组细胞增殖能力,DCFH-DA探针及JC-1染色联合流式细胞术检测GEN对FaDu细胞活性氧(ROS)含量及线粒体膜电位的影响,激光共聚焦显微镜观察GEN对FaDu细胞线粒体膜通透性转换孔的影响,可见分光光度法检测细胞中乳酸的含量,WB法检测细胞中UCP2蛋白的表达变化。结果:与对照组相比,GEN可显著抑制FaDu细胞的增殖活力(P<0.05或P<0.01)、细胞中UCP2蛋白的表达(P<0.05),降低线粒体膜电位(P<0.05或P<0.01)、乳酸含量(P<0.0001),改变细胞线粒体膜孔道通透性,提高细胞中ROS水平(P<0.05或P<0.01)。结论:GEN通过调节细胞中UCP2的表达水平进而影响细胞的氧化还原能力及线粒体功能,从而发挥抑制人下咽癌FaDu细胞增殖并诱导细胞凋亡的作用。

黄连解毒汤6种主要成分高效液相色谱检测方法的建立和应用

目的建立检测黄连解毒汤中6种主要成分的高效液相色谱(HPLC)方法。方法采用Zorbax Eclipse Plus C18色谱柱(250 mm×4.6 mm,5μm),以0.03 mg·mL-1磷酸二氢钾-乙腈(V∶V=7∶3)为流动相,等度洗脱,流速为1.0 mL·min-1,检测波长为345 nm,柱温为37℃,进样量为20μL,建立检测黄连解毒汤6种主要成分(京尼平苷、小檗碱、黄连碱、药根碱、黄芩苷、巴马汀)的HPLC方法。绘制HPLC检测6种成分的标准曲线,并进行方法学评价(线性、加样回收率、准确度和精密度、稳定性)。采用建立的HPLC方法检测黄连解毒汤样本。结果HPLC检测京尼平苷、小檗碱、黄连碱、药根碱、黄芩苷、巴马汀的线性范围分别为25.00~800.00、32.00~1024.00、20.00~640.00、20.30~650.00、13.13~420.00、25.00~800.00μg·mL-1,精密度和准确度均<2%,加样回收率分别为105.30%、102.88%、103.51%、107.76%、96.29%、99.34%。稳定性实验结果显示,室温放置24 h、反复冻融3次、2~8℃保存1周、-80℃冻存1个月,京尼平苷、小檗碱、黄连碱、药根碱、黄芩苷、巴马汀的峰面积相对标准偏差(RSD)均<2%,检测结果均稳定。采用HPLC检测黄连解毒汤的主要成分,浓度从高到低依次为药根碱(2799.00μg·mL-1)、小檗碱(2358.03μg·mL-1)、京尼平苷(1793.34μg·mL-1)、巴马汀(945.30μg·mL-1)、黄连碱(192.00μg·mL-1)、黄芩苷(171.00μg·mL-1)。结论建立的同时检测黄连解毒汤6种主要成分的HPLC方法快速、简便、重复性好、准确度高,可为后续黄连解毒汤的相关研究和临床应用奠定基础。

柔性MXene/壳聚糖/氧化细菌纤维素气凝胶传感器的制备及性能研究

以氧化细菌纤维素、壳聚糖和MXene为基底材料,通过静电相互作用和京尼平化学交联制备高灵敏、稳定的导电气凝胶。利用SEM观察了气凝胶的微观结构,并通过FT-IR、XPS、XRD等手段表征了气凝胶的化学组成及晶型。最后评价了复合气凝胶的压敏性能和人体传感应用。结果表明气凝胶具有较低的质量,其密度仅为1.202 g/cm^(3);其能在500 ms内实现对外力/自身形变的响应;在一定外力范围内,其电阻值在8 000~2 000Ω区间内变化;气凝胶对人体运动进行响应的同时还能区别出不同的运动状态。

1^H NMR-based metabolomics approach to investigating the renal protective effects of Genipin in diabetic rats

Diabetic nephropathy is one of the various complications of diabetes mellitus, affecting patients for lifetime. Earlier studies have revealed that genipin can not only improve diabetes, but also induce cytotoxicity. Therefore, it is not clear which effect of genipin on kidneys occurs, when it is used in the treatment of diabetes. In the present study, we performed nuclear magnetic resonance(NMR)-based metabolomics analysis of urine and kidney tissue samples obtained from diabetic rats to explore the change of endogenous metabolites associated with diabetes and concomitant kidney disease. Nine significant differential metabolites that were closely related to renal function were screened. They were mainly related to three metabolic pathways: synthesis and degradation of ketone bodies, glycine, serine and threonine metabolism, and butanoate metabolism, which are involved in methylamine metabolism, energy metabolism and amino acid metabolism. In addition, after the intervention of genipin, the metabolic levels of all the metabolites tended to be normal, indicating a protective effect of genipin on kidneys. Our results may be helpful for understanding the antidiabetic effect of genipin.

氨基化明胶海绵的制备及其止血性能研究

对明胶进行氨基化改性,同时用京尼平和单宁酸作为交联剂进行交联反应,然后冷冻干燥得到了氨基化明胶海绵。结果表明,该海绵具有丰富的孔状结构以及快速吸水能力,同时能够通过静电相互作用增强与血细胞间的结合能力,使其具有优异的止血性能,为快速止血材料的制备提供了新方法。