Novel affinity-purified antibodies against human SGLT1 (hSGLT1) and SGLT2 (hSGLT2) were used to localize hSGLT2 in human kidney and hSGLT1 in human kidney, small intestine, liver, lung, and heart. ...The renal locations of both transporters largely resembled those in rats and mice; hSGLT2 and SGLT1 were localized to the brush border membrane (BBM) of proximal tubule S1/S2 and S3 segments, respectively. Different to rodents, the renal expression of hSGLT1 was absent in thick ascending limb of Henle (TALH) and macula densa, and the expression of both hSGLTs was sex-independent. In small intestinal enterocytes, hSGLT1 was localized to the BBM and subapical vesicles. Performing double labeling with glucagon-like peptide 1 (GLP-1) or glucose-dependent insulinotropic peptide (GIP), hSGLT1 was localized to GLP-1-secreting L cells and GIP-secreting K cells as has been shown in mice. In liver, hSGLT1 was localized to biliary duct cells as has been shown in rats. In lung, hSGLT1 was localized to alveolar epithelial type 2 cells and to bronchiolar Clara cells. Expression of hSGLT1 in Clara cells was verified by double labeling with the Clara cell secretory protein CC10. Double labeling of human heart with aquaporin 1 immunolocalized the hSGLT1 protein in heart capillaries rather than in previously assumed myocyte sarcolemma. The newly identified locations of hSGLT1 implicate several extra renal functions of this transporter, such as fluid absorption in the lung, energy supply to Clara cells, regulation of enteroendocrine cells secretion, and release of glucose from heart capillaries. These functions may be blocked by reversible SGLT1 inhibitors which are under development.
The initial step in renal secretion of organic anions (OAs) is mediated by transporters in the basolateral membrane (BLM). Contributors to this process are primary active Na(+)-K(+)-ATPase (EC ...3.6.3.9), secondary active Na(+)-dicarboxylate cotransporter 3 (NaDC3/SLC13A3), and tertiary active OA transporters (OATs) OAT1/SLC22A6, OAT2/SLC22A7, and OAT3/SLC22A8. In human kidneys, we analyzed the localization of these transporters by immunochemical methods in tissue cryosections and isolated membranes. The specificity of antibodies was validated with human embryonic kidney-293 cells stably transfected with functional OATs. Na(+)-K(+)-ATPase was immunolocalized to the BLM along the entire human nephron. NaDC3-related immunostaining was detected in the BLM of proximal tubules and in the BLM and/or luminal membrane of principal cells in connecting segments and collecting ducts. The thin and thick ascending limbs, macula densa, and distal tubules exhibited no reactivity with the anti-NaDC3 antibody. OAT1-OAT3-related immunostaining in human kidneys was detected only in the BLM of cortical proximal tubules; all three OATs were stained more intensely in S1/S2 segments compared with S3 segment in medullary rays, whereas the S3 segment in the outer stripe remained unstained. Expression of NaDC3, OAT1, OAT2, and OAT3 proteins exhibited considerable interindividual variability in both male and female kidneys, and sex differences in their expression could not be detected. Our experiments provide a side-by-side comparison of basolateral transporters cooperating in renal OA secretion in the human kidney.
Highlights • Keratinocytes and fibroblasts endogenously express DPP9 transcript and protein. • DPP9 is localized mostly in cytoplasm;its sub-localization in Golgi is very scarce. • DPP8/9 enzyme ...activity was shown in cytosolic fraction of both skin cells types. • DPP8/9 enzyme activity participates in regulation of the skin cells’ proliferation. • DPP9 participates in regulation of adhesion and/or migration of the skin cells.
Serum levels of total prostate specific antigen (t-PSA) and PSA complexed to antichymotrypsin (PSA-ACT), as well as their corresponding density parameters were measured in prostate cancer (PC) ...candidates for radical prostatectomy. In these patients blood Chromogranin A (CgA) values were also recorded. The PSA-ACT recordings in presurgically characterized organ-confined disease were assumed to predict post-surgical staging better than t-PSA. If this proved correct the novel approach might contribute to the positive predictive value of Partin nomograms. In this prospective study 50 patients with clinically localized PC underwent staging pelvic lymphadenectomy and radical prostatectomy. The numerical values of the tPSA and PSA-ACT parameters were presurgically measured. The PSA and PSA-ACT densities (PSAD and ACTD) of the whole prostate were calculated by using transurethral ultrasound (TRUS) data. These preoperative results together with the CgA values were correlated with post-surgical pathological staging data. The relationships between serum tPSA, PSA-ACT, PSAD, ACTD, CgA and the final stage of prostatectomy specimens derived from the pathological data were analyzed. This preliminary study was performed on a relatively small number of patients who were characterized by a serum PSA <20 and a Gleason score (GS) < or =7. Nevertheless, the application of the logistic regression model showed both t-PSA and PSA-ACT to be superior to their density derivatives in predicting postsurgical pathological stage in PC patients who initially seemed to have localized prostate cancer. An elevation in serum CgA level, although rather infrequent at the early stages of PC is principally found in patients with higher Gleason score PC and was mostly associated with extracapsular tumor spread. Our results do not justify the substitution of PSA-ACT for t-PSA data in the Partin nomogram approach.
1 Lunardi and colleagues advanced identification of the eye, inner ear, nervous system and enrr dothelium autoantigens of Cogan syndrome with their finding that the isolated 12rresidue Cogan peptide ...is homologous to four autoantigens: laminin, connexin 26, the collagen diseaserassociated Ssa/Ro, and the receptorrlike phosphatase DEPr 1/CD148, and one viral protein. 1 The agerrelated decrease in testosterone and potential hyporr gonadism may result in decreased libido and erectile dysfunction, loss of muscle mass and strength, weight gain, and declining cognitive funtion.
Luminal acidification in parts of the male reproductive tract generates an appropriate pH environment in which spermatozoa
mature and are stored. The cellular mechanisms of proton (H + ) secretion in ...the epididymis and the proximal vas deferens involve the activity of an apical vacuolar H + ATPase in specialized cell types, as well as an apical Na + /H + exchanger in some tubule segments. In this study we used Western blotting and immunocytochemistry to localize the H + ATPase in various segments of the male reproductive tract in rat and man as a first step toward a more complete understanding
of luminal acidification processes in this complex system of tissues. Immunoblotting of isolated total cell membranes indicated
a variable amount of H + ATPase in various segments of the rat reproductive tract. In addition to its known expression in distinct cell types in the
epididymis and vas deferens, the H + ATPase was also localized at the apical pole and in the cytoplasm of epithelial cells in the efferent duct (nonciliated cells),
the ampulla of the vas deferens and the ventral prostate (scattered individual cells), the dorsal and lateral prostate, the
ampullary gland, the coagulating gland, and all epithelial cells of the prostatic and penile urethra. Both apical and basolateral
localization of the protein were found in epithelial cells of the prostatic ducts in the lateral prostate and in periurethral
tissue. Only cytoplasmic, mostly perinuclear localization of the H + ATPase was found in all epithelial cells of the seminal vesicles and in most cells of the ventral prostate and coagulating
gland. No staining was detected in the seminiferous tubules, rete testis, and bulbourethral gland. In human tissue, H + ATPase-rich cells were detected in the epididymis, prostate, and prostatic urethra. We conclude that the vacuolar H + ATPase is highly expressed in epithelial cells of most segments of the male reproductive tract in rat and man, where it may
be involved in H + secretion and/or intracellular processing of the material endocytosed from the luminal fluid or destined to be secreted by
exocytosis.
Novel affinity-purified antibodies against human SGLT1 (hSGLT1) and SGLT2 (hSGLT2) were used to localize hSGLT2 in human kidney and hSGLT1 in human kidney, small intestine, liver, lung, and heart. ...The renal locations of both transporters largely resembled those in rats and mice; hSGLT2 and SGLT1 were localized to the brush border membrane (BBM) of proximal tubule S1/S2 and S3 segments, respectively. Different to rodents, the renal expression of hSGLT1 was absent in thick ascending limb of Henle (TALH) and macula densa, and the expression of both hSGLTs was sex-independent. In small intestinal enterocytes, hSGLT1 was localized to the BBM and subapical vesicles. Performing double labeling with glucagon-like peptide 1 (GLP-1) or glucose-dependent insulinotropic peptide (GIP), hSGLT1 was localized to GLP-1-secreting L cells and GIP-secreting K cells as has been shown in mice. In liver, hSGLT1 was localized to biliary duct cells as has been shown in rats. In lung, hSGLT1 was localized to alveolar epithelial type 2 cells and to bronchiolar Clara cells. Expression of hSGLT1 in Clara cells was verified by double labeling with the Clara cell secretory protein CC10. Double labeling of human heart with aquaporin 1 immunolocalized the hSGLT1 protein in heart capillaries rather than in previously assumed myocyte sarcolemma. The newly identified locations of hSGLT1 implicate several extra renal functions of this transporter, such as fluid absorption in the lung, energy supply to Clara cells, regulation of enteroendocrine cells secretion, and release of glucose from heart capillaries. These functions may be blocked by reversible SGLT1 inhibitors which are under development.
Objectives To estimate the incidence of transrectal ultrasound (TRUS) hyperechoic lesions and of hyperechoic prostate cancer in TRUS-guided biopsy specimens. Methods We prospectively studied 200 ...patients with total prostate-specific antigen values less than 20 ng/mL and/or positive results on digital rectal examination who had undergone TRUS-guided prostate biopsy. Each patient underwent laterally directed systemic six-core biopsy plus cores from abnormal TRUS lesions and rectally palpable lesions. Six to 10 biopsy cores were obtained from each patient. Results Hyperechoic lesions were found in 19 patients (9.5%), hypoechoic in 83 (41.5%), and isoechoic in 98 (49.0%). Prostate cancer was diagnosed in 33.0% of study patients. Isoechoic findings on TRUS were recorded in 31.8% of patients diagnosed with prostate cancer, whereas 60.6% of cancers had hypoechoic and 7.6% hyperechoic lesions. There was no significant difference in the mean Gleason score between isoechoic cancers (mean 5.4) and hypoechoic cancers (mean 5.6). However, hyperechoic cancers had a mean Gleason score of 7.0, which was higher when compared with isoechoic and hypoechoic cancers. Conclusions Biopsy of hyperechoic lesions was positive for prostate cancer in a higher percentage of patients than previously reported in the literature, and Gleason score of these cancers was higher when compared with isoechoic and hypoechoic cancers.
Luminal acidification in parts of the male reproductive tract generates an appropriate pH environment in which spermatozoa mature and are stored. The cellular mechanisms of proton (H+) secretion in ...the epididymis and the proximal vas deferens involve the activity of an apical vacuolar H+ATPase in specialized cell types, as well as an apical Na+/H+ exchanger in some tubule segments. In this study we used Western blotting and immunocytochemistry to localize the H+ATPase in various segments of the male reproductive tract in rat and man as a first step toward a more complete understanding of luminal acidification processes in this complex system of tissues. Immunoblotting of isolated total cell membranes indicated a variable amount of H+ATPase in various segments of the rat reproductive tract. In addition to its known expression in distinct cell types in the epididymis and vas deferens, the H+ATPase was also localized at the apical pole and in the cytoplasm of epithelial cells in the efferent duct (nonciliated cells), the ampulla of the vas deferens and the ventral prostate (scattered individual cells), the dorsal and lateral prostate, the ampullary gland, the coagulating gland, and all epithelial cells of the prostatic and penile urethra. Both apical and basolateral localization of the protein were found in epithelial cells of the prostatic ducts in the lateral prostate and in periurethral tissue. Only cytoplasmic, mostly perinuclear localization of the H+ATPase was found in all epithelial cells of the seminal vesicles and in most cells of the ventral prostate and coagulating gland. No staining was detected in the seminiferous tubules, rete testis, and bulbourethral gland. In human tissue, H+ATPase-rich cells were detected in the epididymis, prostate, and prostatic urethra. We conclude that the vacuolar H+ATPase is highly expressed in epithelial cells of most segments of the male reproductive tract in rat and man, where it may be involved in H+ secretion and/or intracellular processing of the material endocytosed from the luminal fluid or destined to be secreted by exocytosis.
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