We sought to unravel the role of hydrogen sulfide (H2S) in the development of hypertension in patients with obstructive sleep apnea (OSA).
Methods
The study sample included 80 patients with OSA and 45 healthy controls. All subjects underwent measurement of blood pressure (BP) and serum H2S level in the morning. Twentynine of the 39 patients with OSA and concomitant hypertension and 23 of the 41 patients with OSA but no concomitant hypertension received continuous positive alveolar pressure (CPAP) therapy for 4 weeks. Twenty-four-hour ambulatory BP and serum H2S were determined before and after CPAP. Respiratory indices including apnea hypopnea index (AHI), lowest oxygen saturation (SaO2), and length of time < 90% saturated (T90) were determined by polysomnography.
Results
Associations between H2S, BP, respiratory indices, and changes with CPAP were analyzed. OSA patients had significantly higher systolic BP (p = 0.003) and diastolic BP (p = 0.009) and lower H2S levels (p = 0.02) compared to healthy controls. H2S negatively correlated with AHI (p = 0.005), T90 (p = 0.009), morning systolic BP (p = 0.02), and morning diastolic BP (p = 0.03). All respiratory indices were significantly improved (p < 0.05) after CPAP in OSA patients with or without hypertension. BP was significantly reduced and H2S significantly increased after CPAP in OSA patients with hypertension (p < 0.05) but not in OSA patients without hypertension (p > 0.05).
Conclusion
Multivariate linear regression analysis demonstrated that 24h systolic BP and 24h diastolic BP correlated with H2S as well as their changes after CPAP treatment. Reduction in H2S may play a role in the pathogenesis of hypertension in patients with OSA.
FSH is a key regulator of steroidogenesis and gonadal growth in teleosts. However, function of FSH is elusive in grouper due to the lack of purified and native FSH. In the present study, we reported production of bioactive orange-spotted grouper (Epinephelus coioides) FSH in dimer form and single-chain form by Pichia pastoris. Dimer form of recombinant grouper FSH (rgFSHba) was accomplished by co-expressing mature FSHb-subunit and a-subunit genes. Fusion of mature FSHb-subunit and a-subunit genes together linking with a polypeptide (4×(Gly-Ser)-Gly-Thr) gene generated single-chain form of recombinant grouper FSH (rgFSHb-a). Recombinant grouper common α-subunit (rgCga) and FSHb-subunit (rgFSHb) were also separately produced. Recombinant proteins were verified by Western blot and mass spectrometry assays, and characterized by deglycosylation analysis. Deglycosylation assay suggested that glycosylation of recombinant FSH mainly occurred on common a-subunit. Bioactivities of recombinant proteins were initially evaluated by activating grouper FSH receptor, and further demonstrated by incubating ovarian fragments of adult grouper and intraperitoneal injection in juvenile female grouper. Two forms of recombinant FSH presented similar biological activities of activating FSH receptor and stimulating in vitro testosterone (T) and estradiol-17β (E2) secretion, though the dimer form functioned slightly weaker than the single-chain form. However, injections of rgFSHb-a or rgFSHba could significantly increase serum T and E2 levels, induce early ovarian development, reduce hypothalamic gnrh1 mRNA level, and increase hypothalamic cyp19a1b mRNA level. Data in this study suggested that recombinant gonadotropin could be produced in dimer form or single-chain form by P. pastoris, and FSH could regulate steroidogenesis and early ovarian development in juvenile grouper. 相似文献
Using morpholino antisense oligonucleotide (MO) technology, we blocked leptin A or leptin receptor expression in embryonic zebrafish, and analyzed consequences of leptin A knock-down on fish development. Embryos injected with leptin A or leptin receptor MOs (leptin A or leptin receptor morphants) had smaller bodies and eyes, undeveloped inner ear, enlarged pericardial cavity, curved body and/or tail and larger yolk compared to control embryos of the same stages. The defects persisted in 6-9days old larvae. We found that blocking leptin A function had little effect on the development of early brain (1day old), but differentiation of both the morphant dorsal brain and retinal cells was severely disrupted in older (2days old) embryos. Despite the enlarged pericardial cavity, differentiation of cardiac cells appeared to be similar to control embryos. Formation of the morphants' inner ear is also severely disrupted, which corroborates existing reports of leptin receptor expression in inner ear of both zebrafish and mammals. Co-injection of leptin A MO and recombinant leptin results in partial rescue of the wild-type phenotype. Our results suggest that leptin A plays distinct roles in zebrafish development. 相似文献