Momordica charantia fruit extract with antioxidant capacity improves the expression of tyrosine-phosphorylated proteins in epididymal fluid of chronic stress rats.

OBJECTIVE: Although the protective effects of Momordica charantia L. (MC) extract on chemical-induced testicular damage have been studied, the preventive effects of MC extract on functional proteins in the epididymis under chronic stress have never been reported. This study investigated the protective effects of MC fruit extract on protein secretion, especially tyrosine-phosphorylated proteins, in the epididymis of rats exposed to chronic unpredictable stress (CUS). METHODS: Total phenolic compounds (TPC), total flavonoid compounds (TFC) and antioxidant capacities of MC extract were measured. Adult male rats were divided into 4 groups: control group, CUS group, and 2 groups of CUS that received different doses of MC extract (40 or 80 mg/kg). In treated groups, rats were given MC daily, followed by induction of CUS (1 stressor was randomly applied from a battery of 9 potential stressors) for 60 consecutive days. Plasma corticosterone and testosterone levels were analyzed after the end of experiment. Expressions of heat-shock protein 70 (HSP-70) and tyrosine-phosphorylated proteins present in the fluid of the head and tail of the epididymis were quantified using Western blot. RESULTS: MC extract contained TPC of (19.005 ± 0.270) mg gallic acid equivalents and TFC of (0.306 ± 0.012) mg catechin equivalents per gram, and had 2,2-diphenyl-1-picrylhydrazyl antioxidant capacity of (4.985 ± 0.086) mg trolox equivalents per gram, radical 50% inhibitory concentration of (2.011 ± 0.008) mg/mL and ferric reducing antioxidant power of (23.697 ± 0.819) µmol Fe(II) per gram. Testosterone level in the epididymis was significantly increased, while the corticosterone level was significantly improved in groups treated with MC extract, compared to the CUS animals. Particularly, an 80 mg/kg dose of MC extract prevented the impairments of HSP-70 and tyrosine-phosphorylated protein expressions in the luminal fluid of the epididymis of CUS rats. CONCLUSION: MC fruit extract had antioxidant activities and improved the functional proteins secreted from the head and tail of the epididymis. It is possible to develop the MC fruit extract as a male fertility supplement for enhancing functional sperm maturation in stressed men.

CK2ß Is a Gatekeeper of Focal Adhesions Regulating Cell Spreading.

CK2 is a hetero-tetrameric serine/threonine protein kinase made up of two CK2α/α' catalytic subunits and two CK2ß regulatory subunits. The free CK2α subunit and the tetrameric holoenzyme have distinct substrate specificity profiles, suggesting that the spatiotemporal organization of the individual CK2 subunits observed in living cells is crucial in the control of the many cellular processes that are governed by this pleiotropic kinase. Indeed, previous studies reported that the unbalanced expression of CK2 subunits is sufficient to drive epithelial to mesenchymal transition (EMT), a process involved in cancer invasion and metastasis. Moreover, sub-stoichiometric expression of CK2ß compared to CK2α in a subset of breast cancer tumors was correlated with the induction of EMT markers and increased epithelial cell plasticity in breast carcinoma progression. Phenotypic changes of epithelial cells are often associated with the activation of phosphotyrosine signaling. Herein, using phosphotyrosine enrichment coupled with affinity capture and proteomic analysis, we show that decreased expression of CK2ß in MCF10A mammary epithelial cells triggers the phosphorylation of a number of proteins on tyrosine residues and promotes the striking activation of the FAK1-Src-PAX1 signaling pathway. Moreover, morphometric analyses also reveal that CK2ß loss increases the number and the spatial distribution of focal adhesion signaling complexes that coordinate the adhesive and migratory processes. Together, our findings allow positioning CK2ß as a gatekeeper for cell spreading by restraining focal adhesion formation and invasion of mammary epithelial cells.

Combination of urinary fibrinogen ß-chain and tyrosine-phosphorylated proteins for the detection of bladder cancer.

AIM: To evaluate the performance of urinary fibrinogen ß-chain (FBC) - either alone or associated with urinary tyrosine-phosphorylated proteins (UPY) - as bladder cancer (BCa) diagnostic biomarker. MATERIALS & METHODS: 164 subjects were tested. RESULTS: Significantly different FBC and UPY levels were found between BCa patients and controls, as well as between low-grade and high-grade cancers. The diagnostic accuracy was 0.84 for FBC and 0.87 for UPY. The combination of FBC and UPY improved the accuracy to 0.91. The addition of clinical variables (age, gender, and smoking habit) to FBC and UPY into a model for BCa prediction significantly improved the accuracy to 0.99. The combination of FBC and UPY adjusted for clinical variables associates with the highest sensitivity and good specificity. CONCLUSION: Urinary FBC and UPY could be used as biomarkers for BCa diagnosis.

Decreased expression of AKAP4 and TyrPho proteins in testis, epididymis, and spermatozoa with low sexual performance of mice induced by modified CUMS.

The molecular mechanism of chronic stress especially reduced motility, a major cause of male infertility, has not been proved. It is known that A-kinase anchor protein 4 (AKAP4) and tyrosine-phosphorylated (TyrPho) proteins are involved in progressive motility. This study aimed to investigate the effect of chronic unpredictable mild stress (CUMS) on sexual behaviours, sperm quality, and expressions of AKAP4 and TyrPho proteins in testis, epididymis, and spermatozoa. Sixteen male mice were divided into control and CUMS groups (n = 8/group). Animals were induced by a stressor from twelve stressors for 36 days. Sexual behaviours, corticosterone and testosterone, sperm parameters, and histopathology were observed. The expressions of AKAP4 and TyrPho proteins in testis, epididymis, and spermatozoa were examined. Results showed that CUMS significantly increased corticosterone while serum testosterone level was decreased. Sexual behaviours and sperm parameter quality were significantly decreased. CUMS mice showed vacuolisation and pyknotic cells in seminiferous epithelium and less sperm mass was observed within epididymal lumen. CUMS decreased expressions of AKAP4 and TyrPho proteins in testis, epididymis, and spermatozoa. In conclusion, the decreased expression of AKAP4 and TyrPho proteins may be a mechanism associated with low semen qualities particularly decrease of sperm motility in CUMS.

Effect of chronic stress on expression and secretion of seminal vesicle proteins in adult rats.

Chronic stress (CS) is known to affect men's health especially fertility by reducing semen quality. Although the effects of CS on testicular function and sperm parameters are documented, changes of substances and secreting proteins in the seminal vesicle (SV) have never been reported. This study aimed to demonstrate the alterations of contents and expressions of proteins in seminal vesicle fluid (SVF) under CS. Fourteen adult rats were divided into control and CS groups (n = 7/each). Control rats were not exposed to stressor, while the CS animals were immobilised by restraint cage (4 hr/day) and followed by forced swimming (15 min/day) for consecutive 60 days. Biochemical substances and malondialdehyde (MDA) level in SVF were examined. Expressions of heat-shock protein 70 (Hsp70), caspases (Casp) 3 and 9, and tyrosine-phosphorylated (TyrPho) proteins were investigated in seminal vesicle tissue (SVT) and SVF. It was found that CS caused reductions of seminal epithelial height and secreted substance levels. Significantly, MDA levels in SVF and expressions of Hsp70, Casp and TyrPho proteins were increased in of CS animals. It was concluded that CS affected seminal secretion. Low quality of CS seminal plasma may associate with increase of MDA and expressions of secreted proteins.

Valproic acid changes the expression of tyrosine-phosphorylated proteins in rat seminal vesicle.

Previous studies reported the effects of valproic acid (VPA) on tyrosine-phosphorylated (TyrPho) protein expression in the testis and epididymis, but its effects on that in the seminal vesicle (SV) have never been demonstrated. This study attempted to investigate the expressions of TyrPho proteins in SV treated with VPA. Sixteen rats were divided into control and VPA-treated groups. The control rats were injected with normal saline, whereas the treated animals were intraperitoneally injected with VPA (500 mg/kg BW) for 10 consecutive days (n = 8/each). The biochemical parameters in blood plasma and SV fluid were analysed. The SV tissues and fluid were investigated for the presence and expression of TyrPho proteins, androgen receptor (AR) proteins and heat shock protein 70 (Hsp70). Significantly, VPA caused SV atrophy and reductions in secretion and biochemical parameter levels. There were significant increases in many TyrPho proteins in the plasma (a 95 kDa) and SV tissue (a 40 kDa) of the VPA rats. However, the expressions of seminal AR, Hsp70 and TyrPho proteins (50 and 48 kDa) were significantly lower in VPA rats. Recent results have indicated that VPA affected SV morphology and decreased biochemical fluid substances including TyrPho proteins associated with decreased expressions of AR and Hsp70.

Detection of extracellular vesicles in the mouse vaginal fluid: Their delivery of sperm proteins that stimulate capacitation and modulate fertility.

Extracellular vesicles (EVs) were isolated by ultracentrifugation of vaginal luminal fluid (VLF) from superovulated mice and identified for the first time using transmission electron microscopy. Characterized by size and biochemical markers (CD9 and HSC70), EVs were shown to be both microvesicular and exosomal and were dubbed as "Vaginosomes" (VGS). Vaginal cross-sections were analyzed to visualize EVs in situ: EVs were present in the lumen and also embedded between squamous epithelial and keratinized cells, consistent with their endogenous origin. Western blots detected Plasma membrane Ca2+ -ATPase 1 (PMCA1) and tyrosine-phosphorylated proteins in the VGS cargo and also in uterosomes. Flow cytometry revealed that following coincubation of caudal sperm and VLF for 30 min, the frequencies of cells with the highest Sperm adhesion molecule 1 (SPAM1), PMCA1/4, and PMCA1 levels increased 16.4-, 8.2-, and 27-fold, respectively; compared with control coincubated in phosphate buffered saline (PBS). Under identical conditions, sperm tyrosine-phosphorylated proteins were elevated ~3.3-fold, after VLF coincubation. Progesterone-induced acrosome reaction (AR) rates were significantly (p < 0.001) elevated in sperm coincubated with VGS for 10-30 min, compared with PBS. Sperm artificially deposited in the vaginas of superovulated females for these periods also showed significant (p < 0.01) increases in AR rates, compared with PBS. Thus in vitro and in vivo, sperm acquire from the vaginal environment factors that induce capacitation, explaining recent findings for their acrosomal status in the isthmus. Overall, VGS appear to deliver higher levels of proteins involved in preventing premature capacitation and AR than those promoting them. Our findings which have implications for humans open the possibility of new approaches to infertility treatment with exosome therapeutics.

Localization and changes of tyrosine phosphorylated proteins and ß actin in epididymis of rats treated with valproic acid / Localización y cambios de las proteínas tirosina fosforiladas y la ß actina en epidídimos de ratas tratadas con ácido valproico

Tyrosine phosphorylated proteins have been localized and identified in male reproductive tissues such as testis and capacitated/ acrosome reacted sperm except epididymis. The changes of such proteins are associated with decreased sperm quality of valproic acid treatment. This study aimed to investigate the presence and alterations of protein phosphorylation in epididymal epithelium and fluid of rats treated VPA. Sixteen adult male rats were divided into control and VPA-treated groups (n=8/ each). Treated rats were injected with VPA (500 mg/ kgBW, intraperitoneally) for 10 consecutive days. At the end of experiment, the monoclonal antiphosphotyrosine (clone 4G10) was used for immunohistochemistry to probe tyrosine phosphorylated proteins and also to examine the expression of such proteins using immuno-Western blotting in epididymal tissue and fluid. The result showed that positive reactivity of phosphorylated proteins was clearly observed in cytoplasmic principle cells, nuclei of apical & basal cells and sperm mass surrounded with epididymal fluids. The profiles of phosphorylated proteins in epididymal fluid were 182, 127, 80, 70, 57, 45, 34, and 31 kDas, respectively. Interestingly, VPA affected the changes of phosphorylated proteins and β actin in head, body, and tail epididymal fluids. We conclude that tyrosine phosphorylated proteins were detected in epididymal epithelium and fluid. The expressions of those proteins and actin were altered under VPA treating.

Las proteínas tirosina fosforiladas han sido localizadas e identificadas en tejidos reproductores masculinos tales como testículos y espermatozoides, capacitados a nivel acrosómico, excepto en el epidídimo. Los cambios de estas proteínas están asociadas con una disminución de la calidad del esperma en el tratamiento con ácido valproico (AVP). Este estudio tuvo como objetivo investigar la presencia y las alteraciones de la fosforilación de proteínas en el epitelio epididimal y en el fluido espermático de ratas tratadas con AVP. Dieciséis ratas macho adultas se dividieron en dos grupos: control y tratadas con AVP (n = 8 / cada uno). A las ratas tratadas se les inyectó AVP por vía intraperitoneal (500 mg / kg de peso corporal) durante 10 días consecutivos. Al final del experimento, se realizó inmunohistoquímica con la anti-fosfotirosina monoclonal (clon 4G10) para sondear las proteínas tirosina fosforiladas y también para examinar la expresión de tales proteínas usando inmunotransferencia Western, en tejido y fluido epididimarios. El resultado mostró reactividad positiva de proteínas fosforiladas en células citoplásmicas principales, en los núcleos de las células apicales y basales y en la masa de esperma rodeada por fluidos epididimarios. Los perfiles de proteínas fosforiladas en el fluido epididimal fueron 182, 127, 80, 70, 57, 45, 34 y 31 kDas, respectivamente. El AVP provocó cambios en las proteínas fosforiladas y en la β actina de los fluidos epididimarios de cabeza, cuerpo y cola del epidídimo. Concluimos que las proteínas tirosina fosforiladas se detectaron en el epitelio y el fluido epididimarios. Las expresiones de esas proteínas y de la β actina se alteraron bajo tratamiento con AVP.

Localization and identification of tyrosine phosphorylated proteins in adult Sprague-Dawley rat testis / Localización e identificación de proteínas de tirosina fosforilada en testículos de rata Sprague-Dawley adultos

SUMMARY: Spermatogenesis is a major process in testis occurring from puberty through life span of males. The tyrosine phosphorylation is assumed to play roles in spermatogenesis because this process is important for cell proliferations, divisions, and differentiations. However, the localizations and identifications of phosphorylated proteins in testicular tissue of adult male rats are still unclear. Therefore, this study attempted to immuno-localize and identify such proteins in testicular tissues of Sprague-Dawley rats. The monoclonal anti-phosphotyrosine (clone 4G10) was used to probe tyrosine phosphorylated proteins and also to examine the expression of such proteins using immuno-Western blotting in rat testis. The result showed that positive reactivity of tyrosine phosphorylated proteins was clearly observed in interstitial endocrine cells (Leydig cells), sustentocytes (Sertoli cells), spermatogonia, spermatocytes, and spermatids (round and elongated), respectively. The expressions of testicular tyrosine phosphorylated proteins were 200, 131, 93, 70, 60, and 48 kDas, respectively. In conclusion, testicular tyrosine phosphorylated proteins were localized in both germinal epithelium and interstitial endocrine cells of adult Sprague-Dawley rats.

RESUMEN: La espermatogénesis es un proceso importante en los testículos que ocurre desde la pubertad a lo largo de la vida de los machos. Se supone que la fosforilación de la tirosina desempeña papeles en la espermatogénesis, debido a que este proceso es importante para las proliferaciones, divisiones y diferenciaciones celulares. Sin embargo, las localizaciones e identificaciones de proteínas fosforiladas en el tejido testicular de ratas macho adultas todavía no están claras. Por lo tanto, este estudio intentó inmuno-localizar e identificar dichas proteínas en tejidos testiculares de ratas Sprague-Dawley. La anti-fosfotirosina monoclonal (clon 4G10) se usó para sondar proteínas tirosina fosforiladas y también para examinar la expresión de tales proteínas usando inmunotransferencia Western en testículo de rata. El resultado mostró que la actividad positiva de las proteínas tirosina fosforiladas se observó claramente en endocrinocitos intersticiales (células de Leydig), sustentocitos (células de Sertoli), espermatogonias, espermatocitos y espermátidas (redondas y alargadas), respectivamente. Las expresiones de las proteínas tirosina fosforiladas testiculares fueron de 200, 131, 93, 70, 60 y 48 kDas, respectivamente. En conclusión, las proteínas tirosina fosforiladas fueron localizadas en ambos epitelios germinales y endocrinocitos intersticiales de ratas adultas Sprague-Dawley.