The aim of this prospective study was to assess the duration of culture-viable SARS-CoV-2 and to monitor the emergence of mutations in a cohort of 23 kidney transplant recipients (KTRs) from June 2022 to June 2023. Combined nares/oropharyngeal swabs were collected weekly starting as soon as possible after symptom onset. The time from symptom onset to a negative culture was 11 days (interquartile range, 8-14), while the time to negative reverse transcriptase quantitative polymerase chain reaction was 18 days (interquartile range, 15-30). Beyond the first swab, 21.7% had a positive culture, and 8.7% replicated viable virus for longer than 30 days. T cell depletion (rate ratio, 2.5; 95% confidence interval [95% CI], 1.9-3.3; P < .001) and time from transplantation (rate ratio, 0.93; 95% CI, 0.90-0.97; P = .006) were associated with the time of viable virus shedding. A cycle threshold value of 24.2 demonstrated a 91.3% negative predictive value of viability (95% credible interval [95% CrI], 76-100). The odds of viability decreased by 69% per week of infection (odds ratio, 0.31; 95% CrI, 0.12-0.76). Overall, ribonucleic acid sequencing did not show accelerated molecular evolution though mutation rate could be increased in molnupiravir-treated KTRs. In conclusion, viable SARS-CoV-2 is eliminated rapidly, the risk of virus evolution is low, and prolonged self-isolation is generally unnecessary for most KTRs.
- Klíčová slova
- SARS-CoV-2, immunodeficiency, immunosuppression, infectiousness, kidney transplantation, public health, virus evolution, virus viability,
- Publikační typ
- časopisecké články MeSH
We tested the hypothesis that TAG accumulation in the liver induced by short-term high-fat diet (HFD) in rats leads to the dysregulation of endogenous TAG degradation by lysosomal lipase (LIPA) via lysosomal pathway and is causally linked with the onset of hepatic insulin resistance. We found that LIPA could be translocated between qualitatively different depots (light and dense lysosomes). In contrast to dense lysosomal fraction, LIPA associated with light lysosomes exhibits high activity on both intracellular TAG and exogenous substrate and prandial- or diet-dependent regulation. On standard diet, LIPA activity was upregulated in fasted and downregulated in fed animals. In the HFD group, we demonstrated an increased TAG content, elevated LIPA activity, enhanced production of diacylglycerol, and the abolishment of prandial-dependent LIPA regulation in light lysosomal fraction. The impairment of insulin signalling and increased activation of PKCε was found in liver of HFD-fed animals. Lipolysis of intracellular TAG, mediated by LIPA, is increased in steatosis probably due to the enhanced formation of phagolysosomes. Consequent overproduction of diacylglycerol may represent the causal link between HFD-induced hepatic TAG accumulation and hepatic insulin resistance via PKCε activation.
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Our study focused on the ability of epicardial adipocytes to produce bioactive substances and compare the extent of this production with the production of adipokines in visceral adipocytes, which are well known endocrine cells capable of contributing to the development of atherosclerosis. MATERIAL AND METHODS: The gene expression of human cytokines (IL-6, IL-8, IL-18, RANTES and MCP-1) and adipokines (leptin and adiponectin) was measured in primary cell lines of epicardial and visceral adipocytes, both in undifferentiated and mature statuses, after a 21-day-long differentiation protocol. Each condition was assayed in triplicate in two independent primary cell lines obtained from two different donors. RESULTS: The epicardial preadipocytes showed an increased expression of IL-8 (3.25-fold, p<0.05) compared with visceral preadipocytes. The expression of the atheroprotective adiponectin in epicardial preadipocytes was minimal compared with the expression in visceral preadipocytes (p<0.0001). Moreover, the expression of the genes of interest was dependent on the differentiation degree and cell origin. We observed an altered expression of the proinflammatory genes IL-8 (0.016-fold, p<0.01) and MCP-1 (0.19-fold, p<0.05) in differentiated epicardial adipocytes compared with undifferentiated adipocytes. The epicardial adipocytes showed an increased expression of IL-6 (8.13-fold, p<0.05) compared with the visceral adipocytes. CONCLUSION: Our results suggest that epicardial adipocytes substantially differ from visceral adipocytes and might locally contribute to the pathogenesis of coronary atherosclerosis.
- MeSH
- buněčná diferenciace fyziologie MeSH
- chemokin CCL2 genetika MeSH
- chemokin CCL5 genetika MeSH
- cytokiny genetika MeSH
- dospělí MeSH
- exprese genu fyziologie MeSH
- interleukin-18 genetika MeSH
- interleukin-6 genetika MeSH
- interleukin-8 genetika MeSH
- kultivované buňky MeSH
- lidé MeSH
- nitrobřišní tuk cytologie fyziologie MeSH
- perikard cytologie fyziologie MeSH
- pilotní projekty MeSH
- tukové buňky cytologie fyziologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
- Názvy látek
- CCL2 protein, human MeSH Prohlížeč
- CCL5 protein, human MeSH Prohlížeč
- chemokin CCL2 MeSH
- chemokin CCL5 MeSH
- CXCL8 protein, human MeSH Prohlížeč
- cytokiny MeSH
- IL6 protein, human MeSH Prohlížeč
- interleukin-18 MeSH
- interleukin-6 MeSH
- interleukin-8 MeSH
BACKGROUND: Resident macrophages (Kupffer cells, KCs) in the liver can undergo both pro- or anti-inflammatory activation pathway and exert either beneficiary or detrimental effects on liver metabolism. Until now, their role in the metabolically dysfunctional state of steatosis remains enigmatic. Aim of our study was to characterize the role of KCs in relation to the onset of hepatic insulin resistance induced by a high-fat (HF) diet rich in monounsaturated fatty acids. METHODS: Male Wistar rats were fed either standard (SD) or high-fat (HF) diet for 4 weeks. Half of the animals were subjected to the acute GdCl3 treatment 24 and 72 hrs prior to the end of the experiment in order to induce the reduction of KCs population. We determined the effect of HF diet on activation status of liver macrophages and on the changes in hepatic insulin sensitivity and triacylglycerol metabolism imposed by acute KCs depletion by GdCl3. RESULTS: We found that a HF diet rich in MUFA itself triggers an alternative but not the classical activation program in KCs. In a steatotic, but not in normal liver, a reduction of the KCs population was associated with a decrease of alternative activation and with a shift towards the expression of pro-inflammatory activation markers, with the increased autophagy, elevated lysosomal lipolysis, increased formation of DAG, PKCε activation and marked exacerbation of HF diet-induced hepatic insulin resistance. CONCLUSIONS: We propose that in the presence of a high MUFA content the population of alternatively activated resident liver macrophages may mediate beneficial effects on liver insulin sensitivity and alleviate the metabolic disturbances imposed by HF diet feeding and steatosis. Our data indicate that macrophage polarization towards an alternative state might be a useful strategy for treating type 2 diabetes.
- Publikační typ
- časopisecké články MeSH
Insulin resistance (IR) and consequent hyperinsulinemia are hallmarks of Type 2 diabetes (DM2). Akt kinase (Akt) is an important molecule in insulin signaling, implicated in regulation of glucose uptake, cell growth, cell survival, protein synthesis, and endothelial nitric oxide (NO) production. Impaired Akt activation in insulin-sensitive tissues contributes to IR. However, Akt activity in other tissues, particularly those affected by complications of DM2, has been less studied. We hypothesized that hyperinsulinemia could have an impact on activity of Akt and its effectors involved in regulation of renal morphology and function in DM2. To address this issue, renal cortical Akt was determined in obese Zucker rats (ZO), a model of DM2, and lean controls (ZL). We also studied expression and phosphorylation of the mammalian target of rapamycin (mTOR) and endothelial NO synthase (eNOS), molecules downstream of Akt in the insulin signaling cascade, and documented modulators of renal injury. Akt activity was measured by a kinase assay with GSK-3 as a substrate. Expression of phosphorylated (active) and total proteins was measured by immunoblotting and immunohistochemistry. Renal Akt activity was increased in ZO as compared to ZL rats, in parallel with progressive hyperinsulinemia. No differences in Akt were observed in the skeletal muscle. Corresponding to increases in Akt activity, ZO rats demonstrated enhanced phosphorylation of renal mTOR. Acute PI3K inhibition with wortmannin (100 mug/kg) attenuated renal Akt and mTOR activities in ZO, but not in ZL rats. In contrast to mTOR, eNOS phosphorylation was similar in ZO and ZL rats, despite higher total eNOS expression. In conclusion, ZO rats demonstrated increases in renal Akt and mTOR activity and expression. However, eNOS phosphorylation did not follow this pattern. These data suggest that DM2 is associated with selective IR in the kidney, allowing pro-growth signaling via mTOR, whereas potentially protective effects mediated by eNOS are blunted.
- MeSH
- androstadieny farmakologie MeSH
- diabetes mellitus 2. typu metabolismus MeSH
- hyperinzulinismus metabolismus MeSH
- inhibitory fosfoinositid-3-kinasy MeSH
- inhibitory proteinkinas farmakologie MeSH
- inzulin krev MeSH
- inzulinová rezistence fyziologie MeSH
- krysa rodu Rattus MeSH
- ledviny enzymologie MeSH
- modely nemocí na zvířatech MeSH
- obezita metabolismus MeSH
- potkani Zucker MeSH
- proteinkinasy metabolismus MeSH
- protoonkogenní proteiny c-akt metabolismus MeSH
- signální transdukce fyziologie MeSH
- synthasa oxidu dusnatého, typ III metabolismus MeSH
- TOR serin-threoninkinasy MeSH
- wortmannin MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Názvy látek
- androstadieny MeSH
- inhibitory fosfoinositid-3-kinasy MeSH
- inhibitory proteinkinas MeSH
- inzulin MeSH
- proteinkinasy MeSH
- protoonkogenní proteiny c-akt MeSH
- synthasa oxidu dusnatého, typ III MeSH
- TOR serin-threoninkinasy MeSH
- wortmannin MeSH
BACKGROUND/AIMS: In addition to their lipid-lowering effects, HMG-CoA reductase inhibitors (statins) induce a variety of pleiotropic actions that have been recently studied in the area of cardiovascular and renal protection. In the present studies we sought to determine whether statins retain beneficial effects in the experimental model of NO deficiency achieved by chronic administration of a pressor dose of L-arginine analogue N-nitro-L-arginine-methyl ester (L-NAME). METHODS: To address this issue, blood pressure (BP), renal function (GFR), and albuminuria were determined in rats treated for 4 weeks with L-NAME, L-NAME + atorvastatin (ATO), and in untreated controls. In addition, renal cortical protein expression of caveolin 1 (CAV1), vascular endothelial growth factor (VEGF), and activity of RhoA were also determined. RESULTS: L-NAME administration resulted in sustained elevation of BP, decreased GFR, and in higher albuminuria as compared to control animals. Co-administration of ATO with L-NAME normalized albuminuria and prevented decreases in GFR in L-NAME rats without having an impact on pressor effects of L-NAME. CAV1 protein expression was similar in all groups of rats. In contrast, VEGF expression and RhoA activity was increased in L-NAME-treated animals, and normalized with co-administration of ATO. CONCLUSION: Treatment with ATO exerts early nephroprotective effects in the NO-deficient model of hypertension. These effects could be mediated by amelioration of VEGF expression and reduction of RhoA activity.
- MeSH
- albuminurie farmakoterapie MeSH
- analýza rozptylu MeSH
- atorvastatin MeSH
- glomerulus patologie MeSH
- hodnoty glomerulární filtrace účinky léků MeSH
- hypertenze chemicky indukované prevence a kontrola MeSH
- kaveolin 1 metabolismus MeSH
- krevní tlak účinky léků MeSH
- krysa rodu Rattus MeSH
- kyseliny heptylové farmakologie MeSH
- modely u zvířat MeSH
- nemoci ledvin prevence a kontrola MeSH
- NG-nitroargininmethylester farmakologie MeSH
- oxid dusnatý nedostatek MeSH
- potkani Wistar MeSH
- pyrroly farmakologie MeSH
- rhoA protein vázající GTP metabolismus MeSH
- statiny farmakologie MeSH
- vaskulární endoteliální růstový faktor A metabolismus MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- atorvastatin MeSH
- Cav1 protein, rat MeSH Prohlížeč
- kaveolin 1 MeSH
- kyseliny heptylové MeSH
- NG-nitroargininmethylester MeSH
- oxid dusnatý MeSH
- pyrroly MeSH
- rhoA protein vázající GTP MeSH
- statiny MeSH
- vascular endothelial growth factor A, rat MeSH Prohlížeč
- vaskulární endoteliální růstový faktor A MeSH
BACKGROUND: Cyclooxygenase (COX) isoforms, COX-1 and COX-2, are involved in production of prostanoids in the kidney. Increases in renal COX-2 expression have been implicated in the pathophysiology of progressive renal injury, including type 1 diabetes. Thromboxane A(2) (TxA(2)) has been suggested as the key mediator of these effects resulting in up-regulation of prosclerotic cytokines and extracellular matrix proteins. Unlike type 1 diabetes, renal COX has not been studied in models of type 2 diabetes. METHODS: Renal cortical COX protein expression, and urinary excretion of stable metabolites of prostaglandin E(2) (PGE(2)) and TxA(2), in association with metabolic parameters, were determined in 4-and 12-week-old Zucker fatty rats (fa/fa rat) (ZDF4 and ZDF12), a model of type 2 diabetes, and in age-matched littermates with no metabolic defect (Zucker lean) (ZL4 and ZL12). RESULTS: Western blotting revealed increased COX-2 expression in ZDF4 as compared to ZL4 (245 +/- 130%) (P < 0.05). This increase in COX-2 was even more apparent in 12-week-old ZDF rats (650 +/- 120%) (P < 0.01). All groups of rats demonstrated COX-2-positive cells in typical cortical localizations [macula densa, thick ascending loop of Henle (TALH)]. In contrast to COX-2, COX-1 expression was 30% lower in ZDF12. These changes in COX expression were associated with enhanced urinary excretion of prostanoids, in parallel with the development of metabolic abnormalities. Moreover, increases in prostanoid excretion in ZDF12 were in part reduced by wortmannin (100 mug/kg), used as inhibitor of insulin signaling. CONCLUSION: Renal cortical COX-2 protein expression and function were increased in ZDF rats, as compared to controls, whereas COX-1 exhibited opposite regulation. The changes in COX-2 paralleled metabolic abnormalities, and were at least in part a four consequence of hyperinsulinemia. These abnormalities may play a role in renal pathophysiology in this model of type 2 diabetes.
- MeSH
- androstadieny farmakologie MeSH
- cyklooxygenasa 1 MeSH
- cyklooxygenasa 2 MeSH
- cyklooxygenasy analýza fyziologie MeSH
- dinoproston biosyntéza MeSH
- krysa rodu Rattus MeSH
- kyseliny mastné neesterifikované krev MeSH
- ledviny enzymologie MeSH
- membránové proteiny MeSH
- obezita enzymologie MeSH
- potkani Zucker MeSH
- thromboxan B2 biosyntéza MeSH
- wortmannin MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Research Support, U.S. Gov't, P.H.S. MeSH
- Názvy látek
- androstadieny MeSH
- cyklooxygenasa 1 MeSH
- cyklooxygenasa 2 MeSH
- cyklooxygenasy MeSH
- dinoproston MeSH
- kyseliny mastné neesterifikované MeSH
- membránové proteiny MeSH
- Ptgs1 protein, rat MeSH Prohlížeč
- thromboxan B2 MeSH
- wortmannin MeSH
Genes encoding ferritins were isolated and cloned from cDNA libraries of hard tick Ixodes ricinus and soft tick Ornithodoros moubata. Both tick ferritins are composed of 172 amino-acid residues and their calculated mass is 19,667.2 Da and 19,974.5 Da for I. ricinus and O. moubata, respectively. The sequences of both proteins are closely related to each other as well as to the ferritin from another tick species Dermacentor variabilis (>84% similarity). The proteins contain the conserved motifs for ferroxidase center typical for heavy chains of vertebrate ferritins. The stem-loop structure of a putative iron responsive element was found in the 5' untranslated region of ferritin mRNA of both ticks. Antibodies against fusion ferritin from O. moubata were raised in a rabbit and used to monitor the purification of a small amount of ferritins from both tick species. The authenticity of ferritin purified from O. moubata was confirmed by mass-fingerprinting analysis. In the native state, the tick ferritins are apparently larger (~500 kDa) than horse spleen ferritin (440 kDa). On SDS-PAGE tick ferritins migrate as a single band of about 21 kDa. These results suggest that tick ferritins are homo-oligomers of 24 identical subunits of heavy-chain type. The Northern blot analysis revealed that O. moubata ferritin mRNA level is likely not up-regulated after ingestion of a blood meal.
- MeSH
- druhová specificita MeSH
- elektroforéza v polyakrylamidovém gelu MeSH
- ferritiny genetika MeSH
- klíšťata genetika MeSH
- klonování DNA MeSH
- komplementární DNA MeSH
- messenger RNA genetika MeSH
- molekulární sekvence - údaje MeSH
- northern blotting MeSH
- sekvence aminokyselin MeSH
- sekvence nukleotidů MeSH
- sekvenční homologie aminokyselin MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- ferritiny MeSH
- komplementární DNA MeSH
- messenger RNA MeSH
