The female steroid hormone progesterone regulates ovulation and supports pregnancy, but also controls human sperm function within the female reproductive tract. Progesterone causes elevation of sperm intracellular Ca 2+ leading to sperm hyperactivation, acrosome reaction, and perhaps chemotaxis toward the egg. Although it has been suggested that progesterone-dependent Ca 2+ influx into human spermatozoa is primarily mediated by cationic channel of sperm (CatSper), the principal flagellar Ca 2+ channel of sperm, conclusive loss-of-function genetic evidence for activation of CatSper by progesterone has yet to be provided. Moreover, it is not clear whether the responsiveness of CatSper to progesterone is an innate property of human spermatozoa or is acquired as the result of exposure to the seminal plasma. Here, by recording ionic currents from spermatozoa of an infertile CatSper-deficient patient, we demonstrate that CatSper is indeed the principal Ca 2+ channel of human spermatozoa, and that it is strongly potentiated by progesterone. In addition, by recording CatSper currents from human epididymal and testicular spermatozoa, we show that CatSper sensitivity to progesterone arises early in sperm development and increases gradually to a peak when spermatozoa are ejaculated. These results unambiguously establish an important role of CatSper channel in human sperm nongenomic progesterone signaling and demonstrate that the molecular mechanism responsible for activation of CatSper by progesterone arises early in sperm development concurrently with the CatSper channel itself.CatSper ion channel | male fertility | nongenomic steroid action | sperm physiology
Objective. To describe a unique presentation of neurosarcoidosis. Background. Central nervous system involvement is rare in sarcoidosis. Sarcoidosis can be severe and can be mistaken for systemic lymphoma. Case Description. A 55-year-old right-handed white male with past medical history of obstructive sleep apnea, Raynaud's disease, and Hashimoto's thyroiditis was noted to have cognitive decline over a duration of few weeks and 20 lb weight loss. His neurologic exam (including cranial nerves) was normal except for five-minute recall. Head CT revealed a lacrimal gland mass, confirmed on brain MRI, which was suspicious for lymphoma on brain PET/MRI. Subsequent whole-body FDG PET/CT scan showed multiple enlarged lymph nodes. Bone marrow biopsy was negative. Serum and CSF ACE levels were within normal limits. Supraclavicular lymph node biopsy before steroids therapy was initiated and revealed multiple noncaseating granulomas, diagnostic of “sarcoidosis.” He was treated with daily prednisone for two months, followed by weekly infliximab. Brain MRI two months after treatment with prednisone showed decrease in size of lacrimal lesion, and brain PET/MRI showed normal brain metabolism pattern after five months. Neurocognitive evaluation three months after diagnosis demonstrated improvements in memory abilities. Discussion. Both clinically and radiographically, neurosarcoidosis can mimic systemic lymphoma. Biopsy in these types of cases is necessary to establish the diagnosis.
IL-17A and IL-22 derived from Th17 cells play a significant role in mucosal immunity and inflammation. TGF-β and IL-6 promote Th17 differentiation; however, these cytokines have multiple targets. The identification and screening of additional molecules that regulate IL-17A and IL-22 responses in certain inflammatory conditions is of great clinical significance. In this study, we show that CDDO-Im, a specific Nrf2 activator, promotes IL-17A and IL-22 responses in murine Th17 cells. In contrast, CDDO-Im inhibits IL-17A response in multiple sclerosis patient-derived PBMCs. However, Nrf2 specifically regulates IL-22 response in vivo. Nrf2 acts through the regulation of antioxidant response element (ARE) binding motifs in target genes to induce or repress transcription. Promoter analysis revealed that Il17a, Rorc, and Ahr genes have several ARE motifs. We showed that Nrf2 bound to ARE repressor (ARE-R2) of Rorc and inhibited Rorc-dependent IL-17A transactivation. The luciferase reporter assay data showed that CDDO-Im regulated Ahr promoter activity. Chromatin immunoprecipitation quantitative PCR data showed that Nrf2 bound to ARE of AhR. Finally, we confirmed that the CDDO-Im–mediated induction of IL-22 production in CD4+ T cells was abrogated in CD4-specific Ahr knockout mice (AhrCD4). CH-223191, a specific AhR antagonist, inhibits CDDO-Im–induced IL-22 production in CD4+ T cells, which further confirmed the AhR-dependent regulation. Collectively, our data showed that Nrf2 via AhR pathways regulated IL-22 response in CD4+ T cells.
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