Epidemiology of cercarial stage of trematodes in freshwater snails from Chiang Mai province,Thailand

Objective:To investigate the epidemiological situation of cercarial trematodes infection in freshwater snails from different water resources in Chiang Mai province,Thailand.Methods:The snail specimens were collected from 13 districts of Chiang Mai province during April 2008 to February 2012.The prevalence of cercarial infection in snails was investigated using the crushing method.The drawing was done with the help of a camera lucida for the morphological study.Results:A total of 2479 snail individuals were collected and classified into 7 families,11 genera,and 14 species,Among them,8 snails species were found to be infected with an overall prevalence of 17.27%(428/2479),which infected with nine groups of cercariae;gymnocephalous cercaria,strigea cercaria,megalurous cercaria,monostome cercaria,parapleurolophocercous cercaria(Haplorchis cercaria),pleurolophocercous cercaria,furcocercous cercaria(Transversotrema cercaria),xiphidiocercaria,and virgulate cercaria.The parapleurolophocercous cercaria was found to be the dominant type among the cercarial infection in the snails(64.25%).Conclusions:The various species of snails found in the research location act as the intermediate hosts for the high prevalence of parasitic infection of many species of mammals.This work will provide new information on both the distribution and first intermediate host of trematodes.

Epidemiological situation and molecular identification of cercarial stage in freshwater snails in Chao-Phraya Basin, Central Thailand

Objective: To investigate the prevalence of cercarial trematode infection in snails and to examine the reconstruction of the phylogenetic relationship to explain the molecular system of cercarial stage trematodes to estimate the infection rate of in the definite host from the Chao-Phraya Basin.Methods: The snails were collected from 10 provinces of the Chao-Phraya Basin,Thailand by stratified sampling method. The snails were examined for cercarial infection by the crushing method. All DNA specimens were amplified with internal transcribed spacer 3(ITS3) and ITS4 primer based on PCR technique. The sequence data were aligned and used to reconstruct the phylogenetic tree by unweighted pair-group method with arithmetic means with 10 000 bootstraps.Results: The overall rate of cercarial infection was found to be 5.90%(122/2 067). Snails in the family Thiaridae were found to be in the highest prevalence followed by Lymnaeidae, Bithyniidae, Planorbidae, Viviparidae, and Ampullariidae, respectively, while the Buccinidae family(Clea helena) did not reveal any infections. The frequently found species of cercariae were parapleurolophocercous cercariae, cercariae and megarulous cercariae. The monophyletic tree separated the snails into five groups comprised of Heterophyidae, Strigeidae, Lecithodendriidae, Philophthalmidae and Echinostomatidae using the sequence of Angiostrongylus cantonensis as an out-group.Conclusions: This study was the first to report on cercarial infection in the Chao-Phraya Basin, Thailand. This revealed that a high variety of freshwater snails were infected by cercariae stage trematodes with a high prevalence. The sequence data of ITS2 can be used to investigate the phylogenetic relationships of trematodes at the family level and in each clade of different families separated by the definitive hosts.

Epidemiology and molecular genotyping of echinostome metacercariae in Filopaludina snails in Lamphun Province,Thailand

Objective:To analyze the prevalence of echinostome metacercariae in Filopaludina dorliaris(F.dorliaris)and Filopaludina martensi martensi(F.martensi martensi)and genotype variation of echinostome metacercariae by using random amplified polymorphic DNA(RAPD)analysis.Methods:Filopaludina sp.snails were collected from eight localities of Lamphun Province,Northern Thailand and examined for echinostome metacercariae.RAPD-PCR was used lo analyze genotype variation of echinostome metacercariae.Results:A total of 3 226 F.dorliaris and F.martensi martensi snails were collected from eight localities.The overall prevalences of echinostome metacercariae in F.dorliaris and F.martensi martensi were 40.89%and 36.27%,while the intensity of infection was 20.37 and 12.04,respectively.The dendrogram constructed base on RAPD profiles,4 well supported domains were generated;(i)group of metacercariae from Ban Hong,Mae Ta,Meaung,Pa Sang,Toong Hua Chang,and Weang Nong that were clustered in the group of E.revolutum,(ii)Ban Thi,(iii)Lee,and(iv)3 adults of an out group.Condusioiis:This research demonstrated RAPD profiling has been a useful tool to detect DNA polymorphisms to determine genetic relationship between echinostome metacercariae in Lamphun Province,Northern Thailand.

Prevalence of cercarial infections in freshwater snails and morphological and molecular identification and phylogenetic trends of trematodes

Objective:To investigate the prevalence of cercarial infections in freshwater snails from several water sources in Nakhon Nayok,Nonthaburi,and Pathum Thani provinces of Central Thailand,and to reconstruct a phylogenetic tree for improved understanding of the relationships in the cercarial stage.Methods:The snail specimens were collected from 34 total sampling sites and investigated for cercarial infections using the crushing method.The cercarial specimens were classified and used for the phylogenetic tree analysis using the Internal Transcribed Spacer 2(ITS2).Results:A total of 1921 snail specimens were classified into five families and seven species.The results showed that four snail species were identified as intermediate hosts of the larval stages of trematodes,with an overall prevalence of infection of 2.45%(47/1921).The infected snail specimens included five groups of the cercarial type:cercariaeum cercariae,echinostome cercaria,megalurous cercaria,parapleurolophocercous cercaria,and xiphidiocercariae.This is particularly true of xiphidiocercariae,which was found to be the dominant type among cercarial infections in bithyniid snails by approximately 38.00%.With regard to molecular identification,the phylogenetic tree was reconstructed using the neighbor-joining method with 10000 bootstraps and separated the trematodes into three clades:Echinostomatoidea,Microphalloidea and Opisthorchioidea.Conclusions:The study reveals a high prevalence of cercarial infection for each cercarial type and maturation into a definite trematode genus and delineates morphological characteristics and evolutionary trends among each larval trematode in Nakhon Nayok,Nonthaburi and Pathum Thani provinces.In addition,the ITS2 sequence data of cercariae could be used to examine classification of these species at the family level.

Impact of the photosensitizers hematoporphyrin coated gold nanoparticles on biomphalaria alexandrina snails

The present study was done using two concentrations of the photosensitizer Hematoporphyrin coated Gold Nanoparticles (HpdGNP3) (5x10–6 , 5x10–5 mole/dicemeter–3), to evaluate their efficacy on survival rate, egg-laying capacity of Biomphalaria alexandrina snails and on histological deteriorations in their hermaphrodite gland. B. alexandrina snails were incubated for 12 hours at each tested concentration in the dark, thereafter they were exposed to direct sunlight (336.2 W/m2) for either 2 or 4 hours followed by 24 hours of recovery. Control snails were treated with these concentrations without exposure to light irradiance. Another experiment was carried out simultaneously and the snails were left for 4 weeks of recovery to evaluate their egg-laying capacity (Mx). The results indicate that 5x10–5 Mdm–3 (HpdGNPs) with 4 hours of exposure sunlight suppressed the survival rate of B. alexandrina snails by 50%. Meanwhile, control snails incubated with 5x10–5 Mdm–3 HpdGNPs were not affected and still alive (100%). For snail’s fecundity (Mx), treated snails laid low number of eggs throughout the recov-ery period (4 weeks), in comparison with that of control ones. The highest value of Mx for snails treated with 5x10–5 Mdm–3 Hpd coated GNPs was recorded at the 3rd week of recovery period, being 6.7 eggs/snail, compared to 37.6 eggs/control snail. This has a negative reflect on the reproductive rate (Ro) of treated snails as it was reduced under these conditions by 76.6% and 86.1%, respectively.Histological tests re-vealed injuries in spermatocytes, oocytes, several degenerations of B.alexandrina hermaphrodite gland then evacuations in many gonad’s cells which severely suppressed their capacity for egg-laying. It is concluded from the present work that exposing B. alexandrina snails to sublethal concentrations of the photosensiter Hpd coated GNPs (12 hours incubation, 4 hours exposure to 336.2 W/m2) significantly reduced their reproductive capacity that may have a negative reflect on schistosomiasis transmis-sion.

Occurrence of Biologically Inactive Corrinoid Compounds in Canned Edible Apple Snails (Escargots)

In this study, we characterized and quantified vitamin B12 in canned apple snails, escargots, (boiled plain) using a microbiological assay based on Lactobacillus delbrueckii ATCC 7830. Vitamin B12 contents of canned escargots (boiled plain) were varied from approximately 0.8 μg/100g weight to approximately 5.5 μg/100g weight (mean values, 2.2 μg/100g weight). We identified vitamin B12 compounds from escargots using liquid chromatography-electrospray ionization/tandem mass spectrometry. We found that escargots contained true vitamin B12 and two inactive corrinoids, which were identified as factor IIIm (or methoxymensimidazolyl cyanocobamide), and factor S (or 2-methylmercaptoadenyl cyanocobamide). These results indicate that canned escargots (boiled plain) are not good sources of vitamin B12 for humans.

Corrosion of Snails (Gastropods) in Acidic Environment and Their Protection

Snails’ protection is essential because this species is to maintain a balanced ecology of water sources. They occur in rivers as well as ponds and balance the pH level of water. But these sources of water are contaminated by effluents, pollutants, acid rain, particulates, biological wastes etc. They can change the pH of water. Water is absorber of carbon dioxide and it converts carbon dioxide into carbonic. Other above mentioned wastes also increase the concentration of H+ ions in water. They produce hostile environment for snails. The outer part of snails is made of CaCO3. It produces chemical reaction in acidic medium and corrosion reaction is accelerated, and thus deterioration starts on the surface of snails. This medium makes their survival become miserable. For this work, corrosion of the snails’ study in the pH values of water is 6.5 in H2CO3 environment. The corrosion rates of snails were calculated by gravimetric methods and potentiostat technique. Aloe Vera was used for corrosion protection in acidic medium. The surface adsorption phenomenon was studied by Langmuir isotherm. Aloe Vera formed thin surface film on the interface of snails which adhered with chemical bonding. It was confirmed by activation energy, heat of adsorption, free energy, enthalpy and entropy. The results of surface coverage area and inhibitors efficiency indicated that Aloe Vera developed a strong protective barrier in the acidic medium.

Pollutants, Snails, Oxidative-Stress, Organophosphates, Metals

Aquatic reservoirs remain the ultimate sink of chemical pollutants emanating from anthropogenic activities such as agriculture, mining and industry. Freshwater biota undoubtedly is at risk from the adverse effects of these water pollutants and there is therefore, a need to monitor effects of these chemical pollutants in order to safeguard the health of aquatic biota. We investigated the oxidative stress effects of chlorpyrifos and lead on the freshwater snail Helisoma duryi to assess the potential of using this enzyme system as a biondicator of exposure to environmental pollutants. Groups of snails were exposed to 5 ppb lead acetate and 25 ppb chlorpyrifos for 7 days after which half of the snails were sacrificed and the other half were allowed to recover in clean water and sacrificed after another 7 days. Post mitochondrial fractions were used to measure the activities of the following antioxidant enzymes: superoxide dismutase, catalase, glutathione peroxidase, glutathione S-transferase and diphosphotriphosphodiaphorase. Both pollutants enhanced the activities of all the antioxidant enzymes suggesting a defensive mechanism by the snail to combat the oxidative stress due to the organophosphate chlopryrifos and metal pollutant lead. There was a significant recovery of the antioxidant defense system of the snails allowed to recover in clean water shown by the reduced alteration of the antioxidant enzyme activities of the snails allowed to recover for 7 days. This suggests the need to minimize exposure of aquatic biota to chemical pollutants and remediate the polluted water reservoirs in order to safeguard the health of aquatic life.

Nutritional status of four species of giant land snails in Nigeria

Four species of African giant land snails （Archachatina marginata （ovum ） Pfeiffer, Archachatina marginata （saturalis ） Philippi, Achatina achatina and Limicolaria spp.） were assessed for their proximate and mineral compositions aimed at establishing their nutritive values on wet weight basis. Analysis of muscle revealed that composition of crude protein varied from 18.66%±0.57% in Limicolaria spp. and 20.56%±L0.05% in Archachatina marginata （ovum） Pfeiffer; moisture content was 76.56%±0.04% in Archachatina marginata （ovum） Pfeiffer and 78.68%±0.68% in Limicolaria spp. and ash was 1.34%±0.02% in Achatina achatina and 1.44%±0.01% in Archachatina marginata （ovum） Pfeiffer. These values were statistically different from each other （P〈0.05）. Carbohydrate and fat content were generally low. Crude fibre was not detected in any of the species. The concentrations of zinc, iron, manganese, magnesium, calcium, phosphorus, sulphur, potassium and sodium in the flesh of the snails were determined. Values of iron, magnesium, calcium, phosphorus, potassium and sodium were consistently high while cobalt, copper and lead were not detected. Snails complement the required trace and minor elements needed for proper growth and development in human being, so it is recommended for regular consumption.

Developmental stages and quality traits of giant African land snails [<i>Archachatina marginata</i>(swainson)] eggs

Sixty sexually mature purebred black-skinned Archachatina marginata snails with weight ranging from 120.50 g to 135.70 g were used to generate eggs in this study. The eggs collected were incubated in a chamber filled with loamy soil for appropriate observation and assessment (cracking at four days intervals to check snailet’s development). Results obtained from the study showed that at laying snail egg weights ranged from 1.54 - 2.45 g (mean of 2.00 g). The egg lengths and widths ranged from 13.50 - 16.90 mm (mean of 15.20 mm) and 10.00 - 12.70 mm (mean of 11.40 mm) respectively. The results also revealed that at laying (day one) the egg content was translucent or clear (blank) when observed with light from a powered microscope. Observation of eggs on day four showed the formation of embryo with a semi-transparent cup attached to a long string body. On day 12, some specific organs of the snailet had developed, and there was a reduction in the liquid content. On day 28, the snailet was fully formed, but the shell still contained very small volume of liquid. The snailet hatched on day 29.

Ecology and Species Composition of Fresh Water Snails in Amassoma Community and Niger Delta University Campuses, Bayelsa State, Nigeria

The knowledge about the population dynamics of freshwater snail intermediate host and their roles in disease transmission is little known in Bayelsa State. This study investigated the species composition of fresh water snail intermediate host in Amassoma community and the Niger Delta University Campuses during August 2019-October 2019 across five locations (Main campus Hostel, E.T.F Building, Ogboebi-Ama, Efeke-Ama, Ogbopina). Snails were collected from the water bodies with the aid of a scooping net and hand picking. The morphological identification of the snail intermediate host followed standard procedures. From the result, five hundred and seventy-one freshwater snails belonging to four genera and five species were recorded. The presence of Lymnae and Bulinus in the locations highlights foci for fascioliasis and schistosomiasis. The presence of Melanoides spp. is novel in Bayelsa State. The public health implications of these snails have called for timely control intervention.

New scope on the relationship between rotifers and Biom phalaria alexandrina snails

Objective:To investigate the effect of rotifer internalization into snail tissue on the development of schistosomes.Methods:Susceptible laboratory-bred Biomphalaria alexandrina(B.alexandrina)snails were exposed to lab-maintained rotifers;Philodinaspp.,two weeks before and after being infected with Schistosoma mansoni(S.mansoni)miracidia.The consequent histopathological impact on snail tissues and cercarial biology were investigated before and after emergence from snails.Results:Contamination of B.alexandrinasnails with philodina,two weeks before miracidial exposure,was found to hinder the preliminary development of S.mansonicercariae inside the snail tissues.Furthermore,when snails were contaminated with rotifers two weeks post miracidial exposure;growth of already established cercariae was found to be retarded.The consequent influence of internalized rotifers within the snail tissue was clearly reflected on cercarial em ergence,activity and infectivity along the four weeks duration of shedding.In the present study,comparison of snail histopathological findings and altered cercarial biology observed between the experimental and control groups indicated that the rotifers may have affected the levels of snail's energy reservoirs,which eventually was found to have had an adverse impacton reproduction,growth and survival of the parasite within the snail host,coupled with its performance outside the snail.Conclusions:In future biological control strategies of schistosomiasis,ritifers should be considered as a parasitic scourge of humanity.

Bioavailability of Agricultural Pesticides on the Land Snails in the Commune of Kerou in the North of Benin

The present study was conducted in the commune of Kérou in North Benin to measure the bioavailability of agricultural pesticides heavily used in the production of cotton on snails. The test was conducted in peasant environment in two villages of the commune. In each site, there are three cages containing 6 snails each. The snails are exposed to soil and plants without special protection and are therefore exposed to environmental conditions. Firstly it’s to evaluate the presence or absence of agricultural pesticides in the viscera of snails after exposure. Secondly it consists to compare the different doses found in the viscera of snails in the different sites. And finally it’s to evaluate the effect of the toxicity of the pesticides on the reproduction of snails. The tests consisted of placing steel cages in the two experimental sites. In each site, there are three cages containing 6 snails each. Snails are exposed to soil and plants without special protection and are therefore exposed to environmental conditions. The observations were made in order to establish a study of transfer kinetics. After the analysis of the data, it appears generally that the accumulation of mineral elements highlighted is not proportional to the mineralogical composition of the soil in which the snail is exposed. Total nitrogen and nitrate were significantly accumulated in the flesh of site 2 snails compared to site 1 snails. These different measures show the bioavailability of soil minerals for living organisms. Accumulations are not necessarily accompanied by toxic effects in terms of survival for snails after 28 days of exposure. However, the absence of immediate toxic effect on snails does not imply a lack of effect in food chains due to the trophic availability of contaminants. The use of snails as bio-indicator of soil quality has therefore proved relevant in the context of soils polluted by minerals.

Relationship between Physico-Chemical Parameters and the Population Distribution of Fresh Water Snails in Amassoma Community and Niger Delta University Campuses,Bayelsa State,Nigeria

Evaluating the presence of fresh water snails in a location is germane in establishing a snail-borne disease control program.The purpose of the study was to see how physicochemical parameters influenced the population distribution of four fresh water snails(Lymnaea natalensis,Bulinus globosus,Biomphalaria pfeiffer,and Melanoides spp.)in the Amassoma community and Niger Delta University between March,2021 and May 2021.Snails were gathered by plucking and scooping them by hand.Snail was identified using standard pictorial keys.Physicochemical of the water of the snail habitat were measured using standard in-situ apparatus across eight sites Physico chemical measured were temperature,pH,conductivity,BOD,turbidity,salinity,and alkalinity.A total of 258 snails were gathered from the eight(8)different sites.In all sites,Lymnaea natalensis was more abundant.Bulinus globosus,Biomphalaria pfeiffer,and Melanoides spp.were among the other snails discovered.Lymnaea had negative correlation with pH,conductivity,BOD,and alkalinity and a positive correlation with salinity and temperature.Bulinus had a positive relationship with pH,salinity,and conductivity and a negative correlation with temperature,turbidity,BOD,and alkalinity.Biomphalaria had a positive correlation with temperature,pH,salinity,turbidity,and alkalinity Melanoides had positive correlations with Temperature,pH,salinity,BOD,and alkalinity and a negative correlation with turbidity and concentration.The was correlation between snails and snails.The presence of these snails suggests that the Amassoma village and Niger Delta University campuses are potential hotspots for a variety of snail-borne diseases.

COQ10B在食管鳞癌中的表达及其调控Snail表达促进食管鳞癌细胞增殖与侵袭

目的:探讨COQ10B对食管鳞癌细胞增殖、侵袭能力的影响及可能的分子机制。方法:通过TIMER2.0数据库分析COQ10B基因在各种肿瘤和相邻正常组织之间的表达水平。免疫组织化学检测COQ10B在食管鳞癌组织中的表达水平并进行临床病理特征分析及生存分析;利用慢病毒构建COQ10B敲减稳转株及Snail过表达稳转株,qRT-PCR和Western blot方法检测转染效率。MTT法、Celigo细胞计数及Transwell侵袭小室检测COQ10B对KYSE150细胞系增殖和侵袭能力的影响。通过GEPIA2数据库分析COQ10B表达水平与Snail的相关性;Western blot检测敲减COQ10B对Snail蛋白表达的影响。通过拯救实验分析COQ10B是否通过正调控Snail促进KYSE150细胞系增殖和侵袭能力。结果:COQ10B在ESCC组织及细胞系中均为高表达水平,且表达水平与临床病理特征病理分级相关。COQ10B与ESCC患者预后相关,高表达COQ10B的ESCC患者预后明显较差,且发现性别、肿瘤TNM分期是影响ESCC预后的独立危险因素。敲减COQ10B可降低ESCC细胞增殖及侵袭能力。COQ10B表达水平与Snail呈正相关,并通过正调控Snail促进KYSE150细胞系增殖和侵袭能力。结论:COQ10B通过正向调控Snail基因表达促进食管鳞癌增殖与侵袭。

NEDD8结合酶UBE2F调控肺腺癌转移的分子机制研究

目的:探究NEDD8结合酶UBE2F对肺腺癌(lung adenocarcinoma,LUAD)转移的影响。方法:利用TIMER2.0、UALCAN、HPA等数据库分析UBE2F在肺腺癌中的表达情况;利用Kaplan-MeierPlotter数据库分析UBE2F表达与肺腺癌生存率的关系;运用CRISPR/Cas9技术构建UBE2F敲除的肺腺癌细胞系,并构建UBE2F敲除的裸鼠肺腺癌转移瘤模型,验证UBE2F敲除对肺腺癌转移的影响;通过细胞划痕实验以及Transwell迁移和侵袭实验检测UBE2F敲除对肺腺癌细胞侵袭、迁移能力的影响;Westernblot法和RealtimePCR法检测下调UBE2F表达对上皮-间充质转化(epithelial-mesenchymal transformation,EMT)转录因子Snail表达的影响。结果:多个数据库分析表明,UBE2F在肺腺癌中高表达,且高表达患者比低表达患者具有更好的预后;体内实验表明,与对照组相比,UBE2F敲除后裸鼠肺表面转移的小结节数目显著增多(P<0.05);细胞划痕实验以及Transwell实验表明,UBE2F敲除增强肺腺癌细胞的迁移和侵袭能力,差异具有统计学意义(P<0.05);Westernblot和Re-altimePCR结果显示,UBE2F敲除升高EMT转录因子Snail蛋白水平和mRNA水平。结论:敲除UBE2F诱导Snail积聚,进而导致肺腺癌细胞的侵袭和转移。

秦川牛Snail1克隆、表达特性分析及其对牛脂肪细胞增殖的作用研究

【目的】肉牛肌内脂肪沉积与牛肉的风味、多汁性和嫩度密切相关。脂肪沉积过程表现为脂肪细胞的增殖(数量增多)和分化(脂质生成),受到了多基因协同调控。前人研究发现,小鼠中Snail1可以参与肌肉发育和脂质稳态调控,但其在牛脂肪生成过程中的作用仍未知,有待进一步研究。【方法】以秦川牛为研究对象,克隆得到Snail1 CDS区序列,构建Snail1时空表达谱,运用生物信息学软件对其功能结构及靶基因进行预测。进一步,通过RNAi干扰结合CCK8、EdU、细胞流式及实时荧光定量PCR等方法探究Snail1对牛脂肪细胞增殖的影响。【结果】秦川牛Snail1与NCBI公布序列相比存在2处碱基同义突变,其在秦川牛新生牛肺、肾周脂肪、小肠呈现较高丰度表达;而在成年牛中,Snail1在肾周脂肪组织中的表达量最高,背最长肌中的表达量次之,肺脏组织中的表达量最低。生物信息学分析发现,Snail1启动子区存在1个651 bp CpG岛及C/EBP、PPARα等与脂肪生成相关的转录因子结合位点。CKⅠ(Ser92/96)、CKⅡ(Ser25/119,Thr89)、CDK1(Ser13/104/112/119/143/183/214/221)、CDK5(Ser105/107)等多个细胞周期相关激酶可能参与了Snail1蛋白的磷酸化修饰。通过对牛已注释基因启动子区提取、靶基因预测及KEGG动态网络构建发现,成脂相关的MAPK、PI3K-Akt、mTOR等信号通路为Snail1参与脂肪生成相关的潜在节点信号通路。进一步,通过RNAi干扰试验对其功能研究表明,Snail1下调促进了牛前体脂肪细胞的增殖,增加了复制期阳性细胞的比例(P<0.01)且促进了G1/S细胞周期转换。RT-qPCR和Western-blot检测表明,干扰Snail1显著上调了促增殖调控基因CCNB1、CCND2、CDK2、CDK4(P<0.05)和蛋白的表达。【结论】Snail1在新生牛肾周脂肪及成年牛肾周脂肪和背最长肌中表达量相对较高。干扰Snail1促进了牛前体脂肪细胞的增殖、G1/S细胞周期转变和CCNB1、CCND2、CDK2、CDK4等增殖相关基因表达;CKⅠ、CKⅡ、CDK1/5等多个细胞周期相关激酶可能通过磷酸化修饰Snail1蛋白进而参与细胞增殖调控,而MAPK、PI3K-Akt、mTOR等为Snail1影响牛脂肪细胞增殖潜在的关键节点通路。研究结果为进一步探究Snail1参与牛脂肪生成作用机制奠定了基础。

山奈酚调节AKT/GSK-3β/Snail信号通路对鼻咽癌细胞增殖、凋亡和上皮间质转化的影响

目的:探讨山奈酚对鼻咽癌细胞增殖、凋亡和上皮间质转化(EMT)的影响,并探究其作用机制。方法:将CNE-2细胞分为对照组、山奈酚低浓度组、山奈酚中浓度组、山奈酚高浓度组、山奈酚高浓度+SC-79(AKT激活剂)组。CCK-8法和克隆实验测定细胞增殖,流式细胞术检测细胞凋亡,Western blot检测各蛋白B淋巴细胞瘤-2(Bcl-2)、Bcl-2相关X蛋白(Bax)、天冬氨酸蛋白水解酶-3(Caspase-3)、波形蛋白(Vimentin)、上皮钙黏蛋白(E-cadherin)、神经钙黏蛋白(N-cadherin)、蛋白激酶B(AKT)、磷酸化Akt(p-AKT)、糖原合成酶激酶3β(GSK-3β)、磷酸化GSK-3β(p-GSK-3β)、Snail的表达水平。构建鼻咽癌裸鼠模型,分为裸鼠NC组、山奈酚组、山奈酚+SC-79组,测量肿瘤质量与体积,免疫组化法检测移植瘤组织p-AKT、p-GSK-3β、Snail蛋白表达。结果:山奈酚对人鼻咽癌上皮细胞活力无显著影响(P>0.05);鼻咽癌细胞活力随着山奈酚浓度的升高而逐渐降低(P<0.05),选择CNE-2作为后续实验细胞,选择25、50、100μmol/L山奈酚作为后续实验浓度。与对照组相比,山奈酚低、中、高组细胞活力、Bcl-2、N-cadherin、Vimentin、p-AKT/AKT、p-GSK-3β/GSK-3β、Snail水平显著下降,凋亡率、Bax、Caspase-3、E-cadherin上升(P<0.05);与山奈酚高浓度组相比,山奈酚高浓度+SC-79组细胞活力、Bcl-2、N-cadherin、Vimentin、p-AKT/AKT、p-GSK-3β/GSK-3β、Snail水平显著上升,凋亡率、Bax、Caspase-3、E-cadherin下降(P<0.05)。山奈酚能抑制移植瘤质量和体积,降低p-AKT、p-GSK-3β、Snail蛋白表达(P<0.05);SC-79逆转山奈酚对移植瘤的抑制作用,促进AKT/GSK-3β/Snail通路蛋白表达(P<0.05)。结论:山奈酚能抑制鼻咽癌细胞增殖和EMT,促进细胞凋亡,其作用机制可能与抑制AKT/GSK-3β/Snail信号通路有关。

SOX9通过转化生长因子β信号通路调节角膜内皮损伤后内皮-间质转化过程

目的探究性别决定区Y框蛋白9(sex-determining region Y-box protein 9,SOX9)是否会调控角膜内皮细胞损伤后的角膜上皮-间质转化(endothelial-to-mesenchymal transition,EndMT)过程及具体机制。方法转染小干扰RNA(small interfering RNA,siRNA)敲低人角膜内皮细胞B4G12中SOX9的表达,使用甲萘醌构建体外B4G12细胞损伤模型,设4个分组:si-NC组(转染siRNA-阴性对照)、si-SOX9组(转染siRNA-SOX9)、si-NC+甲萘醌组(转染siRNA-阴性对照后添加外源性甲萘醌做损伤处理)、si-SOX9+甲萘醌组(转染siRNA-SOX9后添加外源性甲萘醌做损伤处理)。通过实时荧光逆转录聚合酶链反应(real-time reverse transcription polymerase chain reaction,RT-PCR)和Western blot检测各组细胞中EndMT关键因子Snail家族转录抑制因子2(snail family transcriptional repressor 2,SNAIL2)及相关信号通路关键因子表达变化,阐明SOX9调控EndMT过程的功能和机制。结果转染siRNA-SOX9敲低细胞SOX9表达后,给予甲萘醌细胞损伤处理,观察到细胞中SNAIL2的表达会随SOX9的敲低而降低,同时观察到转化生长因子β(transforming growth factor beta,TGF-β)信号通路中SNAIL2的上游关键因子Smad2/Smad3的表达也随着SOX9的敲低而降低。结论SOX9通过TGF-β信号通路调控角膜内皮损伤后EndMT过程。

党参炔苷调节AKT/GSK-3β/snail信号通路对胃癌细胞增殖、凋亡和上皮间质转化的影响

目的探究党参炔苷(LOB)调节蛋白激酶B(AKT)/糖原合成酶激酶3β(GSK-3β)/Snail信号通路对胃癌(GC)细胞增殖、凋亡和上皮间质转化(EMT)的影响。方法将GC细胞株SGC7901随机分为对照组(Control组)、低浓度LOB组(LOB-L组,10μmol/L LOB)、中浓度LOB组(LOB-M组,20μmol/L LOB)、高浓度LOB组(LOB-H组,40μmol/L LOB)和高浓度LOB+AKT激活剂SC79组(LOB-H+SC79组,40μmol/L LOB+20μmol/L SC79)。CCK-8法检测5组细胞增殖能力。划痕实验检测细胞迁移能力。Transwell实验检测细胞侵袭能力。流式细胞术检测细胞凋亡。实时荧光定量PCR(RT-qPCR)法测定5组细胞AKT、GSK-3β、snail1 mRNA的表达。Western Blot检测5组细胞AKT/GSK-3β/snail信号通路和凋亡、EMT过程相关蛋白表达。结果与Control组比较,LOB-M组、LOB-H组SGC7901细胞OD450值(48 h、72 h)、细胞划痕愈合率、细胞侵袭数目、AKT、GSK-3β、snail1 mRNA表达和AKT、GSK-3β磷酸化水平、snail1、Bcl-2、N-cadherin、Vimentin蛋白表达显著下降(P<0.05),细胞凋亡率、Bax、E-cadherin蛋白表达显著升高(P<0.05)。SC79减弱了LOB对GC细胞增殖和EMT的抑制作用,抑制了细胞凋亡。结论LOB可能通过下调AKT/GSK-3β/snail信号通路抑制GC细胞增殖和EMT过程,促进细胞凋亡。