Project description:Sweat has a critical role in human body, including thermoregulation and maintenance of skin environment and health. Hyperhidrosis and anhidrosis are caused by abnormalities in sweat secretion resulting in severe skin conditions (pruritus and erythema). Bioactive peptide, pituitary adenylate cyclase-activating polypeptide (PACAP) was isolated and identified to activate adenylate cyclase in pituitary cells. In recent years, it was reported that PACAP increases sweat secretion via PAC1R in mice and promotes the translocation of AQP5 to the cell membrane through increasing intercellular [Ca2+] via PAC1R in NCL-SG3 cells. However, the intracellular signaling mechanisms by PACAP are poorly clarified. In this study, we used PAC1R knockout (KO) mice and wild-type (WT) mice to observe changes in AQP5 localization and gene expression in sweat gland by PACAP treatment. Immunohistochemistry revealed that PACAP promotes the translocation of AQP5 to lumen side in eccrine gland via PAC1R. Furthermore, PACAP up-regulates gene expression (Ptgs2, Kcnn2, Cacna1s) involved in sweat secretion in WT mice. Further, PACAP treatment down-regulated Chrna1 gene expression in PAC1R KO mice. These genes were found to be involved in multiple pathways related to sweating. Overall our data provide a solid basis for future research initiatives to develop new therapies to treat sweating disorders.
Project description:Sweat plays a critical role in human body, including thermoregulation and the maintenance of the skin environment and health. Hyperhidrosis and anhidrosis are caused by abnormalities in sweat secretion, resulting in severe skin conditions (pruritus and erythema). Bioactive peptide and pituitary adenylate cyclase-activating polypeptide (PACAP) was isolated and identified to activate adenylate cyclase in pituitary cells. Recently, it was reported that PACAP increases sweat secretion via PAC1R in mice and promotes the translocation of AQP5 to the cell membrane through increasing intracellular [Ca2+] via PAC1R in NCL-SG3 cells. However, intracellular signaling mechanisms by PACAP are poorly clarified. Here, we used PAC1R knockout (KO) mice and wild-type (WT) mice to observe changes in AQP5 localization and gene expression in sweat glands by PACAP treatment. Immunohistochemistry revealed that PACAP promoted the translocation of AQP5 to the lumen side in the eccrine gland via PAC1R. Furthermore, PACAP up-regulated the expression of genes (Ptgs2, Kcnn2, Cacna1s) involved in sweat secretion in WT mice. Moreover, PACAP treatment was found to down-regulate the Chrna1 gene expression in PAC1R KO mice. These genes were found to be involved in multiple pathways related to sweating. Our data provide a solid basis for future research initiatives in order to develop new therapies to treat sweating disorders.
Project description:Body temperature is maintained in a narrow range in mammals, primarily controlled by sweating. In humans, the dynamic thermoregulatory organ, comprised of 2-4 million sweat glands distributed over the body, can secrete up to 4 liters of sweat per day1, thereby making it possible to withstand high temperatures and run long distances. The genetic basis for sweat gland function, however, is largely unknown. We find that a forkhead transcription factor, FoxA1, is required to generate mouse sweating capacity. When FoxA1 is ablated, mice are otherwise healthy and sweat gland morphogenesis occurs, but no sweating ensues, with the Nkcc1 sodium/potassium/chloride co-transporter and a specialized Ca2+-activated bicarbonate channel protein, Best2, both sharply down-regulated, and glycoprotein accumulating in gland lumens and ducts. Furthermore, Best2 knockout mice display comparable anhidrosis and glycoprotein accumulation. These findings link earlier observations that both sodium/potassium/chloride exchange and Ca2+ are required for sweat production. FoxA1 is inferred to regulate two corresponding features of sweat secretion. One, via Best2, catalyzes a bicarbonate gradient that could help to drive calcium-associated ionic transport; the other, requiring Nkcc1, facilitates monovalent ion exchange into sweat. These mechanistic components can be pharmaceutical targets to defend against hyperthermia and alleviate defective thermoregulation in the elderly2, and may provide a model relevant to more complex secretory processes.
Project description:Body temperature is maintained in a narrow range in mammals, primarily controlled by sweating. In humans, the dynamic thermoregulatory organ, comprised of 2-4 million sweat glands distributed over the body, can secrete up to 4 liters of sweat per day1, thereby making it possible to withstand high temperatures and run long distances. The genetic basis for sweat gland function, however, is largely unknown. We find that a forkhead transcription factor, FoxA1, is required to generate mouse sweating capacity. When FoxA1 is ablated, mice are otherwise healthy and sweat gland morphogenesis occurs, but no sweating ensues, with the Nkcc1 sodium/potassium/chloride co-transporter and a specialized Ca2+-activated bicarbonate channel protein, Best2, both sharply down-regulated, and glycoprotein accumulating in gland lumens and ducts. Furthermore, Best2 knockout mice display comparable anhidrosis and glycoprotein accumulation. These findings link earlier observations that both sodium/potassium/chloride exchange and Ca2+ are required for sweat production. FoxA1 is inferred to regulate two corresponding features of sweat secretion. One, via Best2, catalyzes a bicarbonate gradient that could help to drive calcium-associated ionic transport; the other, requiring Nkcc1, facilitates monovalent ion exchange into sweat. These mechanistic components can be pharmaceutical targets to defend against hyperthermia and alleviate defective thermoregulation in the elderly2, and may provide a model relevant to more complex secretory processes. For expression profiling of FoxA1, hairless fore footpad skin (6) was collected from FoxA1 knockouts and wild-type littermates at P10, P14 and P31. Three skin samples from 3 embryos for each genotype at each time point were used for biological replicates. Total RNAs were isolated with Trizol (Invitrogen), precipitated by 7.5M LiCl (Ambion), and cyanine-3-labeled cRNAs were hybridized to the NIA Mouse 44K Microarray v3.0 (Agilent Technologies). Triplicate data were analyzed by ANOVA (6). Genes with FDR<0.05, fold difference>1.5 and mean log intensity>2.0 were considered to be significant.
Project description:K and Cl channels play critical role for sweat secretion, however, individual K or Cl channels and their functions are largely unknown. By comparing expreession profilings between wild-type and Eda mutant Tabby footpads we identified 4 K and 2 Cl channels highly expressed in mouse eccrine sweat glands.
Project description:K and Cl channels play critical role for sweat secretion, however, individual K or Cl channels and their functions are largely unknown. By comparing expreession profilings between wild-type and Eda mutant Tabby footpads we identified 4 K and 2 Cl channels highly expressed in mouse eccrine sweat glands. Total RNAs isolated from microdissected wild-type and Tabby footpads were profiled with Agilent 44K NIA mouse microarrays.
Project description:Eccrine sweat gland is an exocrine gland that is involved in the secretion of sweat for control of temperature. Malfunction of the sweat glands can result in disorders such as miliaria, hyperhidrosis and bromhidrosis. In addition, lack of reabsorption of Cl- ions from reabsorptive duct of eccrine sweat gland is a major feature of cystic fibrosis. Understanding the proteome of eccrine sweat glands is important for understanding the physiology of sweat formation. In spite of this, no systematic transcriptome or proteome analysis of eccrine sweat glands has yet been reported. To this end, we isolated eccrine sweat glands by microdissecting them from human skin and performed both RNA-seq and proteome analysis. In total, ~138,000 transcripts and ~6,100 proteins were identified. The proteome data showed the enrichment in protein digestion/absorption and salivary secretion, while the transcriptome data did not show any enrichment for a specific pathway. This study also enabled us to confirm 2 missing proteins. Integrating RNA-seq and proteomic data allowed us to identify 7 peptides from 5 novel genes. Most of the novel proteins were from short open reading frames (sORFs) suggesting that many sORFs still remain to be annotated in the human genome. The peptides mapping to the missing or novel proteins were validated by analyzing synthetic peptides. This study provides the first integrated analysis of the transcriptome and proteome of the human eccrine sweat gland and should become an invaluable resource to biomedical research community for studying sweat glands in physiology and disease.
Project description:The potential of eccrine sweat as a bio-fluid of interest for diagnosis and personalized therapy has not yet been fully evaluated, due to the lack of in-depth sweat characterization studies. Thanks to recent developments in the field of omics together with the availability of accredited eccrine sweat collection methods, the analysis of human sweat may now be envisioned as a standardized, non-invasive test for individualized monitoring and personalized medicine. Here, we characterized individual sweat samples, collected from 28 healthy adult volunteers under the most standardized sampling methodology, by applying an optimized Shotgun proteomic analysis. This deep characterization of the sweat proteome allowed the identification of about 1000 unique proteins from which 347 were identified across all samples. Annotation-wise, the study of the sweat proteome unveiled the over-representation of newly addressed Actin dynamics, oxidative stress and proteasome-related functions, in addition to well-described proteolysis and anti-microbial immunity. The sweat proteome composition appeared to be correlated to the inter-individual variability of sweat secretion parameters (water and solute losses). Besides, both gender-exclusive proteins and gender-specific protein abundances were highlighted in spite of the high similarity between human female and male sweat proteomes. In conclusion, standardized sample collection coupled to optimized shotgun proteomics significantly improved the depth of sweat proteome coverage, far beyond previous similar studies. The identified proteins were involved in many diverse biological processes and molecular functions indicating the potential of this bio-fluid as a valuable biological matrix for further studies. Addressing sweat variability, our results prove the proteomic profiling of sweat to be a promising bio-fluid for individualized, non-invasive monitoring and personalized medicine.
Project description:The eccrine sweat gland is an exocrine gland that is involved in the secretion of sweat for control of temperature. Malfunction of the sweat glands can result in disorders such as miliaria, hyperhidrosis and bromhidrosis. In addition, inadequate reabsorption of salt from sweat is a major feature of cystic fibrosis. Understanding the transcriptome and proteome of sweat glands is important for understanding the physiology and the role in disease. However, no systematic transcriptome or proteome analysis of sweat glands has yet been reported. To this end, we isolated eccrine sweat glands by microdissecting them from human skin and performed both RNA-seq and proteome analysis. In total, ~138,000 transcripts and ~6,100 proteins were identified. The proteome data of eccrine sweat gland showed enrichment of proteins involved in secretion, reabsorption, and wound healing while the transcriptome data did not show any enrichment for a specific pathway. Importantly, protein level identification of TRPV4 in eccrine sweat gland establishes its importance in re-epithelialization of partial-thickness wound and prevention of dehydration. Furthermore, this study enabled us to identify2 missing proteins. Integration of RNA-seq and proteomic data allowed us to identify 7 peptides from 5 novel genes. Most of the novel proteins were from short open reading frames (sORFs) suggesting that many sORFs still remain to be annotated in the human genome. The peptides mapping to the missing or novel proteins were validated by analyzing synthetic peptides. This study provides the first integrated analysis of the transcriptome and proteome of the human eccrine sweat gland and should become an invaluable resource to biomedical research community for studying sweat glands in physiology and disease.