Regulation of Metabolic Homeostasis in Cell Culture Bioprocesses.
O'Brien Conor M,Mulukutla Bhanu Chandra,Mashek Douglas G,Hu Wei-Shou
Trends in biotechnology
Mammalian cells are the main tool for the production of therapeutic proteins, viruses for gene therapy, and cells for cell therapy. In production processes cell metabolism is the main driver that causes changes in the growth environment and affects productivity and product quality. Of all nutrients, glucose has the most prominent impact on bioprocesses. We summarize recent findings on the regulation of glucose and energy metabolism in cultured cells. Local allosteric regulations and post-translational modifications of enzymes in metabolic networks interplay with global signaling and transcriptional regulation. These regulatory networks sustain homeostasis across the cytosolic and mitochondrial compartments. Understanding the regulation of glucose metabolism and metabolic state is crucial for enhancing process productivity and product quality.
Integrated Pharmacodynamic Analysis Identifies Two Metabolic Adaption Pathways to Metformin in Breast Cancer.
Lord Simon R,Cheng Wei-Chen,Liu Dan,Gaude Edoardo,Haider Syed,Metcalf Tom,Patel Neel,Teoh Eugene J,Gleeson Fergus,Bradley Kevin,Wigfield Simon,Zois Christos,McGowan Daniel R,Ah-See Mei-Lin,Thompson Alastair M,Sharma Anand,Bidaut Luc,Pollak Michael,Roy Pankaj G,Karpe Fredrik,James Tim,English Ruth,Adams Rosie F,Campo Leticia,Ayers Lisa,Snell Cameron,Roxanis Ioannis,Frezza Christian,Fenwick John D,Buffa Francesca M,Harris Adrian L
Late-phase clinical trials investigating metformin as a cancer therapy are underway. However, there remains controversy as to the mode of action of metformin in tumors at clinical doses. We conducted a clinical study integrating measurement of markers of systemic metabolism, dynamic FDG-PET-CT, transcriptomics, and metabolomics at paired time points to profile the bioactivity of metformin in primary breast cancer. We show metformin reduces the levels of mitochondrial metabolites, activates multiple mitochondrial metabolic pathways, and increases 18-FDG flux in tumors. Two tumor groups are identified with distinct metabolic responses, an OXPHOS transcriptional response (OTR) group for which there is an increase in OXPHOS gene transcription and an FDG response group with increased 18-FDG uptake. Increase in proliferation, as measured by a validated proliferation signature, suggested that patients in the OTR group were resistant to metformin treatment. We conclude that mitochondrial response to metformin in primary breast cancer may define anti-tumor effect.
Metabolic pathways and immunometabolism in rare kidney diseases.
Grayson Peter C,Eddy Sean,Taroni Jaclyn N,Lightfoot Yaíma L,Mariani Laura,Parikh Hemang,Lindenmeyer Maja T,Ju Wenjun,Greene Casey S,Godfrey Brad,Cohen Clemens D,Krischer Jeffrey,Kretzler Matthias,Merkel Peter A,
Annals of the rheumatic diseases
OBJECTIVES:To characterise renal tissue metabolic pathway gene expression in different forms of glomerulonephritis. METHODS:Patients with nephrotic syndrome (NS), antineutrophil cytoplasmic antibody-associated vasculitis (AAV), systemic lupus erythematosus (SLE) and healthy living donors (LD) were studied. Clinically indicated renal biopsies were obtained at time of diagnosis and microdissected into glomerular and tubulointerstitial compartments. Microarray-derived differential gene expression of 88 genes representing critical enzymes of metabolic pathways and 25 genes related to immune cell markers was compared between disease groups. Correlation analyses measured relationships between metabolic pathways, kidney function and cytokine production. RESULTS:Reduced steady state levels of mRNA species were enriched in pathways of oxidative phosphorylation and increased in the pentose phosphate pathway (PPP) with maximal perturbation in AAV and SLE followed by NS, and least in LD. Transcript regulation was isozymes specific with robust regulation in hexokinases, enolases and glucose transporters. Intercorrelation networks were observed between enzymes of the PPP (eg, transketolase) and macrophage markers (eg, CD68) (r=0.49, p<0.01). Increased PPP transcript levels were associated with reduced glomerular filtration rate in the glomerular (r=-0.49, p<0.01) and tubulointerstitial (r=-0.41, p<0.01) compartments. PPP expression and tumour necrosis factor activation were tightly co-expressed (r=0.70, p<0.01). CONCLUSION:This study demonstrated concordant alterations of the renal transcriptome consistent with metabolic reprogramming across different forms of glomerulonephritis. Activation of the PPP was tightly linked with intrarenal macrophage marker expression, reduced kidney function and increased production of cytokines. Modulation of glucose metabolism may offer novel immune-modulatory therapeutic approaches in rare kidney diseases.