Macrophages produce and secrete proteoglycans. They are involved in inflammation and may contribute to the glycosaminoglycans (GAG) and proteoglycans (PG) characteristic of the inflamed area. This possible contribution was studied with rat peritoneal macrophages (pMP) in vitro. The total amount, composition, and neosynthesis of the GAG (as the main constituents of PG) were determined in cultured pMP of normal rats or rats pretreated with casein, BCG, thioglycolate or carrageenan. Partly the stimulated pMP were further activated with LPS or PMA. The rat pMP contained non-sulfated GAG, chondroitin sulfate and heparan sulfate but no dermatan sulfate. The GAG amount per cell increased with duration of the culture. In most cases the final level of GAG roughly corresponded to that of 12 micrograms hexuronic acid per 10(6) cells. It was lower after BCG stimulation (25%) and higher in pMP stimulated by both casein and LPS (200%). The average percentage of the GAG secreted (40%) was enhanced with pMP stimulated by carrageenan (87%) or casein plus LPS (69%). The pattern of the GAG in cultural media, cell coat and cells differed markedly. Thus the cell coat contained a higher amount of heparan sulfate. Differences due to stimulation were mainly seen in the reduced sulfation of the CS-proteoglycan secreted (casein-, BCG-pMP). According to studies on the incorporation of 35S-sulfate and 3H-acetate the GAG of the cell coat are less labeled and more conservative. The bulk of newly synthesized GAG/PG is secreted. This secretion appears an important property of macrophages the cause of which is speculative.
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Int J Biol Macromol
January 2025
Department of Physiology, Navy Medical University, Shanghai 200433, China. Electronic address:
In the mammalian cardiovascular system, endothelial glycocalyx is a gel-like layer that covers the luminal surface of endothelial cells (ECs) and plays crucial roles in vascular homeostasis, permeability and leukocyte adhesion. Degradation of this structure occurs early in sepsis and becomes accordingly dysfunctional. In severe cases, it is not self-regulated by the organism.
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Renal Pathophysiology Laboratory, Hospital das Clínicas, University of São Paulo School of Medicine, São Paulo, Brazil.
In glomerulopathies, endothelial dysfunction and the presence of histological vascular lesions such as thrombotic microangiopathy, arteriolar hyalinosis, and arteriosclerosis are related to a severe clinical course and worse renal prognosis. The endothelial cell, which naturally has anti-inflammatory and anti-thrombotic regulatory mechanisms, is particularly susceptible to damage caused by various etiologies and can become dysfunctional due to direct/indirect injury or a deficiency of protective factors. In addition, endothelial regulation and protection involve participation of the complement system, factors related to angiogenesis, the renin-angiotensin system (RAS), endothelin, the glycocalyx, the coagulation cascade, interaction between these pathways, interactions between glomerular structures (the endothelium, mesangium, podocyte, and basement membrane) and interstitial structures (tubules, arterioles and small vessels).
View Article and Find Full Text PDFAging Cell
January 2025
Department of Biobehavioral Health, Penn State University, University Park, Pennsylvania, USA.
Epigenetic clocks are a common group of tools used to measure biological aging-the progressive deterioration of cells, tissues, and organs. Epigenetic clocks have been trained almost exclusively using blood-based tissues, but there is growing interest in estimating epigenetic age using less-invasive oral-based tissues (i.e.
View Article and Find Full Text PDFNat Cell Biol
January 2025
State Key laboratory of Genetic Engineering, School of Life Sciences, Liver Cancer Institute of Zhongshan Hospital, Fudan University, Shanghai, China.
Severe damage to the intrahepatic biliary duct (IHBD) network occurs in multiple human advanced cholangiopathies, such as primary sclerosing cholangitis, biliary atresia and end-stage primary biliary cholangitis. Whether and how a severely damaged IHBD network could reconstruct has remained unclear. Here we show that, although the gallbladder is not directly connected to the IHBD, there is a common hepatic duct (CHD) in between, and severe damage to the IHBD network induces migration of gallbladder smooth muscle cells (SMCs) to coat the CHD in mouse and zebrafish models.
View Article and Find Full Text PDFVet Res Commun
January 2025
Department of Veterinary Medicine, University of Perugia, Via San Costanzo, 4, Perugia, 06126, Italy.
This study describes the congenital goiter in an alpaca (Vicugna pacos) fetus aborted in November 2021 with the clinical and pathological findings in the dam that was found dead on the farm three weeks after a miscarriage. The dam was a black coat alpaca bred in the Netherlands, imported in Italy in January 2021, and housed in a farm of central Italy for breeding purposes. Signalment and clinical data on dam and fetus were collected from the farmer and referring veterinarian.
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