OBJECTIVE: Zinc-α2-glycoprotein (ZAG) has been proposed as a tumour-derived cancer cachexia factor. However, ZAG is produced by some normal tissues, including white adipose tissue (WAT), and high serum ZAG levels are present in nonmalignant conditions. We determined whether human WAT contributes to serum ZAG levels and how serum and WAT-secreted ZAG levels correlate with catabolism in patients with cancer and in obese subjects undergoing a very low-calorie diet (VLCD) for 11 days. DESIGN/ SUBJECTS: ZAG levels in serum and in conditioned medium from WAT/adipocytes were determined by enzyme-linked immunosorbent assay. ZAG release from WAT in vivo was determined in 10 healthy subjects. The correlation between ZAG and cachexia was studied in 34 patients with newly diagnosed gastrointestinal cancer. The impact of a VLCD on ZAG release and serum levels was assessed in 10 obese women. RESULTS: ZAG was released from abdominal WAT and adipocytes in vitro. However, the arteriovenous differences in vivo showed that there was no significant contribution of WAT to the circulating levels. WAT-secreted but not serum ZAG correlated positively with poor nutritional status but not with fat mass (or body mass index) in patients with gastrointestinal cancer. In obese subjects on a VLCD, ZAG secretion from WAT increased significantly whereas serum levels remained unaltered. CONCLUSIONS: ZAG is released from human WAT, but this tissue does not contribute significantly to the circulating levels. WAT-secreted ZAG correlates with nutritional status but not with fat mass in both cancer and nonmalignant conditions. Adipose ZAG is therefore a local factor activated primarily by the catabolic state per se.
OBJECTIVE: Zinc-α2-glycoprotein (ZAG) has been proposed as a tumour-derived cancer cachexia factor. However, ZAG is produced by some normal tissues, including white adipose tissue (WAT), and high serum ZAG levels are present in nonmalignant conditions. We determined whether human WAT contributes to serum ZAG levels and how serum and WAT-secreted ZAG levels correlate with catabolism in patients with cancer and in obese subjects undergoing a very low-calorie diet (VLCD) for 11 days. DESIGN/ SUBJECTS:ZAG levels in serum and in conditioned medium from WAT/adipocytes were determined by enzyme-linked immunosorbent assay. ZAG release from WAT in vivo was determined in 10 healthy subjects. The correlation between ZAG and cachexia was studied in 34 patients with newly diagnosed gastrointestinal cancer. The impact of a VLCD on ZAG release and serum levels was assessed in 10 obesewomen. RESULTS:ZAG was released from abdominal WAT and adipocytes in vitro. However, the arteriovenous differences in vivo showed that there was no significant contribution of WAT to the circulating levels. WAT-secreted but not serum ZAG correlated positively with poor nutritional status but not with fat mass (or body mass index) in patients with gastrointestinal cancer. In obese subjects on a VLCD, ZAG secretion from WAT increased significantly whereas serum levels remained unaltered. CONCLUSIONS:ZAG is released from human WAT, but this tissue does not contribute significantly to the circulating levels. WAT-secreted ZAG correlates with nutritional status but not with fat mass in both cancer and nonmalignant conditions. Adipose ZAG is therefore a local factor activated primarily by the catabolic state per se.
Authors: X Ke; L Duan; F Gong; Y Zhang; K Deng; Y Yao; L Wang; F Feng; B Xing; H Pan; H Zhu Journal: J Endocrinol Invest Date: 2022-06-07 Impact factor: 5.467
Authors: Steve H Faulkner; Kate L Spilsbury; James Harvey; Andrew Jackson; Jingfeng Huang; Mark Platt; Alfred Tok; Myra A Nimmo Journal: Eur J Appl Physiol Date: 2014-03-01 Impact factor: 3.078
Authors: Peter Arner; Frauke Henjes; Jochen M Schwenk; Spyros Darmanis; Ingrid Dahlman; Britt-Marie Iresjö; Peter Naredi; Thorhallur Agustsson; Kent Lundholm; Peter Nilsson; Mikael Rydén Journal: PLoS One Date: 2015-04-21 Impact factor: 3.240
Authors: Thomas Daniel Kraemer; Inga Soerensen-Zender; Nima Memaran; Hermann Haller; Anette Melk; Bernhard Magnus Wilhelm Schmidt; Roland Schmitt Journal: Front Cardiovasc Med Date: 2021-07-05