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Contains fulltext : 293805.pdf (Publisher’s version ) (Open Access) OBJECTIVE: Thyroid hormone (TH) transport represents a critical first step in governing intracellular TH regulation. It is still unknown whether the full repertoire of TH transporters has been identified. Members of the solute carrier (SLC) 22 family have substrates in common with the known TH transporters of the organic anion-transporting peptide family. Therefore, we screened the SLC22 family for TH transporters. METHODS: Uptake of 1 nM of iodothyronines or sulfated iodothyronines in COS1 cells expressing SLC22 proteins was performed. RESULTS: We first tested 25 mouse (m) SLC22 proteins for TH uptake and found that the majority of the organic anion transporter (OAT) clade were capable of 3,3',5-triiodothyronine and/or thyroxine (T4) transport. Based on phylogenetic tree analysis of the mouse and human (h) SLC22 family, we selected eight hSLC22s that grouped with the newly identified mouse TH transporters. Of these, four tested positive for uptake of one or more substrates, particularly hSLC22A11 showed robust (3-fold over control) uptake of T4. Uptake of sulfated iodothyronines was strongly (up to 17-fold) induced by some SLC22s, most notably SLC22A8, hSLC22A9, mSLC22A27 and mSLC22A29. Finally, the zebrafish orthologues of SLC22A6/8 drOatx and drSlc22a6l also transported almost all (sulfated) iodothyronines tested. The OAT inhibitors lesinurad and probenecid inhibited most SLC22 proteins. CONCLUSIONS: Our results demonstrated that members of the OAT clade of the SLC22 family constitute a novel, evolutionary conserved group of transporters for (sulfated) iodothyronines. Future studies should reveal the relevance of these transporters in TH homeostasis and physiology.

Background and aims: Homozygous familial hypercholesterolemia (HoFH) is characterized by severely elevated low-density lipoprotein cholesterol (LDL-C) levels leading to extremely premature atherosclerotic cardiovascular disease. Therefore, healthcare professionals consider HoFH to have major impact on patients’ life. Remarkably, little is known on how patients deal with their condition. The aim of this study is to investigate how Dutch patients experience and cope with HoFH in daily life. Methods: Adult patients with genetically confirmed HoFH, treated at the 3 specialized HoFH-centers in the Netherlands, were interviewed in-depth. Interview transcripts were analyzed according to grounded theory. Health-related quality of life (QoL) and coping were measured with the EuroQol (EQ)-5D-5L questionnaire and the Threatening Medical Situations Inventory (TMSI), respectively. Results: 20 Dutch HoFH patients were interviewed: 50% women, median age 38 years, 60% with cardiovascular disease, 10% on apheresis. Coding of the transcripts resulted in a conceptual model, with disease perception as the central theme. Individual TMSI-results corresponded to the interviews, with most patients showing both monitoring (information-seeking behavior) and blunting (distractive strategies) coping styles. The median EQ-5D-5L health utility score (0.839) was only 5% below the Dutch population (0.887). Transient anxiety was reported when confronted with the consequences of HoFH in daily life. Patients reported high confidence in treatment by a dedicated HoFH center, which helped them cope with their disease. Conclusions: Dutch HoFH patients use a variety of effective coping mechanisms in such a way that their subjective QoL is only slightly affected. Healthcare professionals can use this knowledge to tailor their care to the specific needs of these patients.

Contains fulltext : 198215.pdf (Publisher’s version ) (Open Access)