Expression of calpains and calpastatin in diaphragm of a rat model of COPD / 实用医学杂志

Objective To investigate the expression of calpains and calpastatin in diaphragm of a rat model of chronic obstructive pulmonary disease(COPD). Methods Fotry male Wistar rats were randomly divided into the control group and the COPD group. Rats in the COPD group were copied by expo -sing to cigarettes smoking and dripping lipopolysaccharide into trachea. Pathological changes of lung and diaphragm were deteted. Immunohis-tochemistry and RT-PCR were performed to determine protein and mRNA expression of calapins and calpastatin. Results Diaphragmatic atrophy was observed in rats in the COPD group instead of the control group. The protein and mRNA expression of calpains in diaphrag-m of COPD group were Increased than those in the control group(P < 0.05). On the contrary ,the expression of calpastatin was significantly reduced in rats in the COPD group(t =-9.38 and-2.97;P < 0.001 ,P = 0.005). Conclusions An imbalance in the expression of calpains/calpastatin in diaphragm was observed in COPD rats ,and this imbalance may be responsible for diaphragm atrophy.

Neuroprotective effect of Spilanthes acmella Murr. on pesticide-induced neuronal cells death

Objective To investigate protective effects of Spilanthes acmella (S. acmella) Murr. extracts against pesticide-induced neuronal cells death and to elucidate the underlying molecular mechanism in dopaminergic (SH-SY5Y) cells lines. Methods Cell viability of SH-SY5Y cells was studied by treating the cells with various concentration of pirimicarb for 24 h. Neuroprotective effect of S. acmella Murr. extracts was investigated by adding the plant extracts to the medium for 24 h prior to the incubation with 100 μM H

Neuroprotective effect of Spilanthes acmella Murr. on pesticide-induced neuronal cells death

OBJECTIVE@#To investigate protective effects of Spilanthes acmella (S. acmella) Murr. extracts against pesticide-induced neuronal cells death and to elucidate the underlying molecular mechanism in dopaminergic (SH-SY5Y) cells lines.@*METHODS@#Cell viability of SH-SY5Y cells was studied by treating the cells with various concentration of pirimicarb for 24 h. Neuroprotective effect of S. acmella Murr. extracts was investigated by adding the plant extracts to the medium for 24 h prior to the incubation with 100 μM HO or with pirimicarb for 24 h. Control-untreated cells were incubated with the culture medium. Cell viability was measured by MTT assay, calpain and calpastatin expressions were analyzed by Western blotting and immunocytochemistry.@*RESULTS@#Pretreatment of SH-SY5Y cells with S. acmella Murr. extracts (1 μg/mL) for 24 h significantly increased the dopaminergic neurons in pirimicarb-induced neurotoxicity. In addition, pretreatment with the S. acmella Murr. extracts led to decreased calpain but increased calpastatin protein levels.@*CONCLUSION@#S. acmella Murr. extracts exerted neuroprotective effect, via an alteration of calcium homeostasis, against pirimicarb induced neurotoxicity. The S. acmella Murr. might be a potential natural candidate with neuroprotective activity.

Meat tenderness genetic polymorphisms occurrence and distribution in five Zebu breeds in Mexico

Background The Zebu cattle are represented by a diverse group of breeds in México. Traditionally these breeds have been associated with the tough beef characteristic. Validated genetic markers have the potential to be included in marker-assisted selection and management programs in order to improve traits such as beef tenderness. The incidence and distribution of Calpain and Calpastatin polymorphisms strongly associated with beef tenderness were estimated in registered cattle of five Zebu breeds in Mexico. Results A low and in some cases null frequency of favorable C allele of CAPN316 was determined in all breeds. Conversely, a more equilibrated frequency in CAPN4751 and CAST loci was observed. Conclusions Although the relatively low occurrence of favorable alleles in assessed loci may limit their use in selection programs, genotyping availability might be a practical and comprehensive tool for introgression programs by marker assisted selection and management as to improve meat tenderness of Zebu breeds.

Establishment and identification of calpastatin transgenic mouse models / 中国实验动物学报

Objective To establish an animal model of calpastatin ( CAST) transgenic mice by inserting the full hu-man CAST into the genome of C57BL/6J mice.Methods Recombinant transgenic vector pRP .EX3d-EF1A-CAST-IRES-eGFP was constructed by Gateway technology .It was injected into the fertilized eggs from C 57BL/6J mice.The injected eggs were transplanted into the oviduct of pseudopregnant mice .Tail DNA PCR screening was performed to identify the positive founder mice.The expressions of CAST mRNA and protein in tissues of the transgenic mice were detected by RT -PCR and Western blotting.Results Ninty eggs were transplanted into the oviducts of 3 recipients.The transplantation success rate was 100%.23 viable offsprings were born from the recipients .Tail DNA PCR screening showed that two of the offsprings were positive transgenic mice .The positive rate of transgenic mice was 9%.RT-PCR assay revealed that CAST mRNA ex-pressions were present in the heart , liver, kidney, lung, spleen, brain and skeletal muscle of the transgenic mice .Addition-ally, the CAST protein expression was significantly increased in the transgenic mice .Conclusion CAST transgenic mice have been successfully established and provide a good animal model support for further studies on the CAST function .

Calpastatin gene is not associated with late onset sporadic Parkinson' s disease in Chinese Han population / 中华行为医学与脑科学杂志

Objective To explore the association between late-onset sporadic Parkinson' s disease (PD) and single nucleotide polymorphisms (SNPs) of Ca2+-dependent protease calpain inhibitor calpastatin (CAST) gene in a Chinese Han population.Methods 370 evaluable patients (221 male,149 female) with PD (mean age 65.2 ± 8.5 years) and 390 neurologically healthy controls (208 male,182 female) matched for gender,ethnicity,and area of residence.PD cases were identified from the PD cohort of the Chinese National Consortium on Neurodegenerative Diseases (www.chinapd.cn).A total of 24 tag-SNPs were genotyped capturing 95％ of the genetic variation across the CAST gene.Results There was no association found between any of the polymorphisms and PD in all models tested (co-dominant,dominant-effect and recessive-effect (P ＞ 0.05)).Similarly,none of the common haplotypes was associated with a risk for PD(P ＞ 0.05).Conclusion Results show no significant association between the CAST gene polymorphisms and late onset sporadic PD in the present population.

Implications of calpains in health and diseases.

The number of mammalian calpain protease family members has grown as many as 15 till recent count. Although initially described as a cytosolic protease, calpains have now been found in almost all subcellular locations i.e., from mitochondria to endoplasmic reticulum and from caveolae to Golgi bodies. Importantly, some calpains do not possess the 28 kDa regulatory subunit and have only the 80 kDa catalytic subunit. In some instances, the 80 kDa subunit by itself confers the calpain proteolytic activity. Calpains have been shown to be involved in a number of physiological processes such as cell cycle progression, remodeling of cytoskeletal-cell membrane attachments, signal transduction, gene expression and apoptosis. Recent studies have linked calpain deficiencies or it’s over production with a variety of diseases, such as muscular dystrophies, gastropathy, diabetes, Alzheimer’s and Parkinson’s diseases, atherosclerosis and pulmonary hypertension. Herein, we present a brief overview on some implications of calpains on human health and some diseases.

The inhibitory role of sympathetic nervous system in the Ca2+-dependent proteolysis of skeletal muscle

Mammalian cells contain several proteolytic systems to carry out the degradative processes and complex regulatory mechanisms to prevent excessive protein breakdown. Among these systems, the Ca2+-activated proteolytic system involves the cysteine proteases denoted calpains, and their inhibitor, calpastatin. Despite the rapid progress in molecular research on calpains and calpastatin, the physiological role and regulatory mechanisms of these proteins remain obscure. Interest in the adrenergic effect on Ca2+-dependent proteolysis has been stimulated by the finding that the administration of β2-agonists induces muscle hypertrophy and prevents the loss of muscle mass in a variety of pathologic conditions in which calpains are activated. This review summarizes evidence indicating that the sympathetic nervous system produces anabolic, protein-sparing effects on skeletal muscle protein metabolism. Studies are reviewed, which indicate that epinephrine secreted by the adrenal medulla and norepinephrine released from adrenergic terminals have inhibitory effects on Ca2+-dependent protein degradation, mainly in oxidative muscles, by increasing calpastatin levels. Evidence is also presented that this antiproteolytic effect, which occurs under both basal conditions and in stress situations, seems to be mediated by β2- and β3-adrenoceptors and cAMP-dependent pathways. The understanding of the precise mechanisms by which catecholamines promote muscle anabolic effects may have therapeutic value for the treatment of muscle-wasting conditions and may enhance muscle growth in farm species for economic and nutritional purposes.

Expression of calpain and calpastatin in arthritis and antigen epitopes of human calpastatin recognized by rheumatoid arthritis sera / 中华风湿病学杂志

Objective To compare the expression level of calpain and calpastatin mRNA in rheumatoid arthritis (RA) and osteoarthritis (OA) synovial tissues (ST) and analyze the antigen epitopes of human calpastatin recognized by RA sera.Methods Total RNA of three RA and two OA patients was isolated from ST and expression levels of calpain and calpastatin mRNA were detected by reverse transcription polymerase chain reaction (RT PCR).According to hydrophilicity of human calpastatin (Accession,U 31346), overlapping oligopeptides were synthesized by auto spot Robot in N terminal (L domain) and C terminal (Ⅳ domain) of calpastatin.The epitopes of synthesized peptides were analyzed by RA sera using dot ELISA.Results mRNA expression of calpain showed higher than that of calpastatin in both OA and RA.Meanwhile,the mRNA expression level of calpain increased in RA more than that in OA.Three antigen epitopes of human calpastatin (with the sequence DKDLDDALD,DTIPPEYRH and QDPIDALSG) were identified by RA sera,while control sera failed to react with synthetic peptides.Conclusion The calpain calpastatin system may participate in pathogenic mechanism of RA,and the calpastatin may be a target for autoantibody of RA,which implies that it is not only possible to treat RA patients with synthetic peptide of human calpastatin,as a chemotherapeutant,but also a materials for immunodiagnosis of RA.